Search for dissertations about: "high speed modulation"

Showing result 1 - 5 of 100 swedish dissertations containing the words high speed modulation.

2. 1. Efficient 1.3 mm GaInNAs Quantum Well Lasers for Uncooled, High Speed Operation

   Author : Yongqiang Wei; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; semiconductor laser; uncooled; temperature dependence; modulation; quantum well; molecular beam epitaxy; high speed; GaInNAs;

   Abstract : The rapid expansion of tele and data transmission systems requires an ever increasing capacity in modern optical fibre communication networks. With the implementation of short distance, high density networks, such as access networks, there is a need for cost-effective optical transmitters compatible with single mode fibres. READ MORE

4. 2. VCSEL Cavity Engineering for High Speed Modulation and Silicon Photonics Integration

   Author : Emanuel Haglund; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high-speed modulation; on-chip laser source; vertical-cavity surface-emitting laser VCSEL ; semiconductor lasers; optical interconnects; large signal modulation; laser dynamics; heterogeneous integration; vertical-cavity silicon-integrated laser VCSIL ; silicon photonics;

   Abstract : The GaAs-based vertical-cavity surface-emitting laser (VCSEL) is the standard light source in today's optical interconnects, due to its energy efficiency, low cost, and high speed already at low drive currents. The latest commercial VCSELs operate at data rates of up to 28 Gb/s, but it is expected that higher speeds will be required in the near future. READ MORE

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

   Author : Marco Forzati; Chalmers tekniska högskola; []
   Keywords : 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;

   Abstract : 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. 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. VCSELs for High-Speed, Long-Reach, and Wavelength-Multiplexed Optical Interconnects

   Author : Erik Haglund; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; mode filter; high-contrast grating; oxide aperture; high-speed modulation; wavelength control; spectral width; vertical-cavity surface-emitting laser; optical interconnect; quasi-single-mode;

   Abstract : The vertical-cavity surface-emitting laser (VCSEL) is the standard light source in short-reach fiber-optic links in datacenters and supercomputers. These systems use an enormous number of links, making cost and energy efficiency pressing issues. READ MORE