Sökning: "high order modulation"

Visar resultat 1 - 5 av 179 avhandlingar innehållade orden high order modulation.

1. 1. The alternate-phase return-to-zero modulation format in high-speed optical-fibre communications

   Författare :Marco Forzati; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high-speed optical transmission; return-to-zero; nonlinear optics; dispersion management; phase modulation; modulation formats; Fibre optics communication; fibres;

   Sammanfattning : Increasing the channel bit rate is an efficient way to upgrade traffic capacity in installed transmission links. At bit rates of the order of 40 Gb/s, on-off keying transmission becomes severely impaired by non-linear effects,particularly Intra-channel Cross-Phase Modulation (IXPM) and Intra-channel Four-Wave Mixing (IFWM), which cause pulses in different bit slots to interact with each-other. LÄS MER

3. 2. Control, Modulation and Implementation of Modular Multilevel Converters

   Författare :Antonios Antonopoulos; Hans-Peter Nee; Colin Oates; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Modular Multilevel Converter; Modulation; Feedback Control; Open-Loop Control; Implementation; Prototype; High-Performance Motor Drives; Electrical engineering; electronics and photonics; Elektroteknik; elektronik och fotonik;

   Sammanfattning : Denna avhandling behandlar analys och styrning av den modulära multinivå omvandlaren (M2C). M2C är en lovande omvandlarteknologi för högspända högeffekttillämpningar. Anledningen till detta är låg distorsion i utstorheterna kan uppnås med låg  medelswitchfrekvens per switch och utan utgångsfilter. LÄS MER

4. 3. Phase Modulation Techniques for On-Off Keying in Optical Fibre Transmission

   Författare :Marco Forzati; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; return-to-zero; fibre optics communication; phase modulation; nonlinear optics; dispersion management; high-speed optical transmission; modulation formats; fibres;

   Sammanfattning : Increasing the channel bit rate is an efficient way to upgrade traffic capacity in installed transmission links. At bit rates of the order of 40 Gb/s, on-off keying (OOK) transmission becomes severely impaired by non-linear effects especially Intra-channel Four-Wave Mixing (IFWM) which limit the power at which the signal can be transmitted, and ultimately the transmission distance. LÄS MER

5. 4. Multi-Gigabaud Millimeter-Wave Communication - Challenges and Solutions

   Författare :Jingjing Chen; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; phase noise; high-order modulation; 5G; multi-gigabaud; PAM-4; high data rate; white noise; multi-gigabit; phase noise mitigation; 64-QAM; mobile backhaul; VCSEL driver; Frequency multiplier; modem; high frequency oscillator; multiplicative noise; power detector; fronthaul; millimeter-wave communication;

   Sammanfattning : A major challenge in future mobile networks is to overcome the capacity barrier in wireless communication. Utilizing large bandwidth at higher frequencies is key to enabling capacity upgrade for next generation mobile networks (5G). LÄS MER

7. 5. High-efficiency Power Amplification Techniques for Wireless Transmitters

   Författare :Hossein Mashad Nemati; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; load modulation; LDMOS; supply modulation; GaN HEMT; Power amplifier; wireless communications.; GaAs mHEMT; efficiency;

   Sammanfattning : The low efficiency of existing power amplifiers (PAs) is causing excessive energy consumption in wireless systems. Improving the PA efficiency is therefore of great environmental and economical importance. LÄS MER