Research On Radio Over Free Space Optical Communication System

Recently, transmission of radio frequency(RF) signals over free space optical(FSO) link, which is also referred as radio over FSO, has got a great deal of research attentions. It has been proposed as one of the solutions for last-mail applications. RoFSO communication system can transfer radio signals with high transmission capacity and low cost without changing radio format. In this thesis, we introduce the theory of the RoFSO system and analyse its performance based on the analysis of the atmosphere channel.Firstly, we introduce the RoFSO system and analyse its theory. The theories of the transmitters and receivers are discussed with different modulations. We also present the optical antennas which actually are telescopes.Secondly, we analyse the attenuation and intensity fluctuation effect which degrade the performance of RoFSO system. Additionally, the bit error rate(BER) and outage probability are derived for the RoFSO system. We also give the expression of the link margin for the RoFSO system. We also have a comparison with the FSO system.Then, we study the spatial diversity reception technology and the all-optical multihop RoFSO system with amplify-and-forward relays. The BER and outage probability have been gotten in closed form expressions using generalized power series. Both the numerical result and the simulation result are gotten to prove the improvement of the performance.In the end, we introduce the theory of the distributed jamming system based on the RoFSO and design a RoFSO link. In this thesis, we also design an examination hall distributed jamming system and test the experiment system.