Free-space optical propagation of pulse coded data stream

2003 ◽  
Author(s):  
Xiaohui Ni ◽  
Qirong Xing ◽  
Wei Cai ◽  
R. R. Alfano
2015 ◽  
Vol 738-739 ◽  
pp. 1178-1184
Author(s):  
Ru Hai Guo ◽  
Chang Shun Liu ◽  
Heng Kun Wang ◽  
Jin Wu ◽  
Jun Feng Chong

A new transceiving protocol is designed for an FSO communication system, and it’s discussed from the transmitting protocol and the receiving protocol. Different from wired communication, a FSO system modulates the data on a narrow beam of laser transmitting through the free space or the atmosphere, and the protocol is optimized for terrestrial FSO links. Due to the complex composition and activity of the atmosphere, this signal channel brings in great influence on the transmitting laser in it. The function of the receiving protocol includes filtering and synchronizing the input serial data stream, paralleling the serial data stream, decoding the input data, error checking, and exception handling and interfacing the outer receiver with a parallel port. The transceiving protocol could be programmed into a single FPGA chip to improve system integrity and reduce the system cost. We also test the hardware platform and communication protocol and give the waveform. The experiment and Simulation prove that the protocol presented can work well at a certain bit rate scale.


2020 ◽  
Vol 3 ◽  
pp. 69-74
Author(s):  
Thoalfiqar Ali Zaker ◽  
Talib Zeedan Taban ◽  
Firas S. Mohammed

This study estimates the performance of a free space optical system (FSO) affected by air pollutants from oil fires. Simulations are performed to evaluate the reliability of optical propagation according to the length of the FSO channels under two beam angle angles. The proposed FSO system parameters such as the Q-factor, BER and reception capacity are successfully used to reduce channel loss. Results demonstrate that the proposed FSO link performs satisfactorily when the divergence angle is 1 mrad and the distance is from 0.5 km to 0.9 km. Q-factor and receiving power decrease when the divergence angle of beam increases to 2 mrad, and a link is achieved when the distance is from 0.5 km to 0.7 km. The eye diagram is used to evaluate and confirm the quality of received data. An eye opening is observed at 0.5 km for both divergence angles. Then, the eye completely closes at 1 km for 2 mrad, thereby degrading the performance. Therefore, these results can be conducted for similar systems optimization options by applying our analysis


2008 ◽  
Vol 47 (31) ◽  
pp. 5736 ◽  
Author(s):  
Makoto Akiba ◽  
Kayo Ogawa ◽  
Kazuhiko Wakamori ◽  
Kashiko Kodate ◽  
Shigeo Ito

Author(s):  
Matthew Higgins ◽  
Zeina Rihawi ◽  
Zaiton Abdul Mutalip ◽  
Roger Green ◽  
Mark S. Leeson

This chapter reviews some of the network topologies and technologies within current vehicular systems. This is then followed by a proposal from the authors with initial viability results, into the possibility of implementing optical wireless links to either replace or complement these existing ideas. The initial motivation for this work (Green, 2010) is that there exist multiple pathways within a vehicle such as the engine compartment, within the frame of the chassis, or the internal cockpit that all lend themselves nicely to free space optical propagation. The first specialised study on the viability of optical wireless communications within the vehicles cabin was then published in (Higgins et al, 2012) which provided a further impetus to the concept. It is hoped that through the original results presented here, the reader can gain a basic understanding of the concepts compared to the current technologies, and are then able instigate their own research ideas.


Author(s):  
Pirmin Pezzei ◽  
Clemens Wurster ◽  
Michael Wollitzer ◽  
Martin Fuchs ◽  
Erich Leitgeb

2009 ◽  
Vol 4 (8) ◽  
Author(s):  
Muhammad Saleem Awan ◽  
Laszlo Csurgai Horwath ◽  
Sajid Sheikh Muhammad ◽  
Erich Leitgeb ◽  
Farukh Nadeem ◽  
...  

Sign in / Sign up

Export Citation Format

Share Document