14543

13121

كارشناسي ارشد

مخابرات

اصفهان : دانشگاه صنعتي اصفهان

1397

يازده، 93ص. : مصور،‌ جدول،‌ نمودار

مسعود عمومي

اصغر غلامي

نغمه السادات مويديان، فروغ السادات طباطبا

1398/02/03

كتابنامه

برق

مهندسي برق و كامپيوتر

1398/02/04

2526753

Investigation and Simulation of Different Approaches for Modulation and Transferring Signals in Radio Over Fiber and Terahertz Systems Mohamadreza Fatehi mohamadreza fatehi@ec iut ac ir Jan 20 2019 Department of Electrical and Computer Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor Masood Omoomi omoomi@cc iut ac ir Abstract Transferring RF and THz signals over optical fiber is an efficient solution to provide high data rate for wireless networkusers Considering the recent advances in microwave photonics and optical communication technology transmission ofradio signals in different frequency bands has a bright future Based on expected performance cost complexity acceptablenoise carrier frequency and data rate different kinds of modulation can be used Hence in radio over fiber networks andTHz systems many designs with different transmitters and receivers have been proposed In this thesis after explainingbackground and applications of transferring RF and THz signals over optical fiber main features of basic devices used inthis networks including optical sources optical fibers photodetectors Mach Zehnders and optical amplifiers have beenexplained Optical direct intensity ODSB OSSB OCS and phase modulation using one optical source and direct detectionhave been introduced Optical direct and coherent detection using two optical sources with their applications in THz systemsand enhancing radio over fiber networks have been introduced To compare these different modulation types 5 Gbps databy an OFDM signal in a radio over fiber system by direct intensity ODSB OSSB and phase modulations has been sent Simulation results have shown that direct intensity modulation is suitable for transferring data in short distances In higherdistances up to 55 Km ODSB modulation without any optical amplifier has a BER lower than 1 10 3 By increasingthe distance between optical transmitter and receiver and using 5dB and 10dB amplifiers BER lower than 1 10 3 upto 63 and 70 Km has been achieved respectively In OSSB modulation without optical amplifier and with 5dB and 10dBamplifiers acceptable BER for 40 km has been attained in 2 4 GHz frequency band OSSB modulation has shown a betterperformance compared to ODSB modulation in 30 GHz frequency band Phase modulation has a better performance andby 5dB and 10dB amplifiers 1 10 3 BER for 75 and 90 km has been reached respectively Finally in a Terahertz systemby sending 5 and 10 Gbps data in baseband 1 10 9 BER for 9 8 and 4 km has been achieved respectively Key Words Microwave Photonics Radio over Fiber THz systems Wireless Networks

مسعود عمومي

اصغر غلامي

نغمه السادات مويديان، فروغ السادات طباطبا