Search for dissertations about: "coherent detection"

Showing result 1 - 5 of 83 swedish dissertations containing the words coherent detection.

2. 1. Fiber-Optic Systems with Coherent Detection and Four-Dimensional Modulation

   Author : Martin E Sjödin; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; intradyne; polarization-switched QPSK; quadrature phase-shift keying QPSK ; coherent detection; self-homodyne; wavelength-division multiplexing; 16-ary quadrature amplitude modulation; self-phase modulation; 128-SP-QAM; polarization multiplexing; pilot tone;

   Abstract : To increase the data rates of fiber-optic communication systems, modulation formats withhigher spectral efficiency and/or higher power efficiency than binary formats are of greatinterest. These formats require coherent detection and this thesis has been dedicated toinvestigating both novel modulation formats and two different types of coherent systems. READ MORE

4. 2. Coherent CO2 laser radar in active imaging systems

   Author : Dietmar Letalick; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Q-switching; atmospheric turbulence; coherent laser radar; terrain segmentation; heterodyne detection; range-based object detection; imaging laser radar; co2 laser;

   Abstract : .... READ MORE

5. 3. Multidimensional Modulation Formats for Coherent Optical Communication Systems

   Author : Tobias Eriksson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; binary pulse position modulation QPSK; Fiber-optical communication; spectral efficiency; power efficiency; multidimensional position modulation.; 16-ary quadrature amplitude modulation 16QAM ; quadrature phase shift keying QPSK ; coherent detection; polarization-switched quadrature phase shift keying PS-QPSK ; 128-level set-partitioning QAM 128-SP-QAM ;

   Abstract : Coherent optical receivers have enabled the use of multilevel modulation formats with high spectral efficiencies and long transmission reaches. Traditionally, modulation formats utilizing the two dimensions spanned by the amplitude and the phase of the signal have been dominating. READ MORE

6. 4. Multi-level modulation formats for high-speed optical transmission systems

   Author : Ekawit Tipsuwannakul; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; quadrature amplitude modulation; spectral efficiency; differential detection; modulation format; coherent detection; phase shift keying;

   Abstract : Over the past several years, the use of multi-level modulation formats has enabledsignificant improvements in the field of optical fiber communication, particularlyin terms of per-channel bit-rate (i.e., line-rate) and spectral efficiency (SE), byencoding multiple bits per symbol. READ MORE

7. 5. Aspects of Power Consumption in Coherent Fiber-Optical Communication Systems

   Author : Lars Lundberg; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; optical frequency comb; Fiber-optical communication; power consumption; carrier-recovery; Raman amplification; energy-efficiency; optical amplifier; digital signal processing; coherent detection; erbium-doped fiber amplifier; phase-tracking;

   Abstract : The power consumption of coherent fiber-optical communication systems is becoming increasingly important, for both environmental and economical reasons. The data traffic on the Internet is increasing at a faster pace than that at which optical network equipment is becoming more energy efficient, which means that the overall power consumption of the Internet is increasing. READ MORE