Sökning: "optical communications"

Visar resultat 1 - 5 av 69 avhandlingar innehållade orden optical communications.

1. 1. Signaling for Optical Intensity Channels

   Författare :Johnny Karout; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; lattice codes; mutual information; intensity modulation; noncoherent communications; Direct detection; sphere packing.; infrared communications; free-space optical communications; fiber-optical communications;

   Sammanfattning : With the growing popularity of social media services, e-commerce, and many other internet-based services, we are witnessing a rapid growth in the deployment of data centers and cloud computing platforms. As a result, the telecommunications industry has to continue providing additional network capacity to meet the increasing demand for bandwidth. LÄS MER

3. 2. Modulation Optimization for Noncoherent Optical Systems

   Författare :Johnny Karout; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct detection; noncoherent communications; lattice codes; mutual information; fiber-optical communications; intensity modula- tion; sphere packing.; infrared communications; free-space optical communications;

   Sammanfattning : There has been a significant improvement in high-speed electronics and optical components over the past few years, and this is one of the key enabling factors for high data rate transmission. Moreover, multi- level modulation formats, which encode information onto the carrier’s amplitude and phase, are necessary to increase the spectral efficiency of communication systems. LÄS MER

4. 3. High-capacity short-reach optical communications

   Författare :Rui Lin; Jiajia Chen; Lena Wosinska; Yu Yu; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; optical communication; optical frequency comb; radio-over-fiber; optical interconnect; fiberoptisk kommunikation; optisk frekvenskams; Radio-över –fiber; passiva optiska interconnects; Informations- och kommunikationsteknik; Information and Communication Technology;

   Sammanfattning : The global traffic is experiencing an exponential growth posing severe challenges to the communication networks in terms of capacity. As a future-proof technology fiber communication is widely implemented in different network segments, which can be categorized by transmission distance as long-haul and short-reach. LÄS MER

5. 4. Phase Noise Tolerant Modulation Formats and DSP Algorithms for Coherent Optical Systems

   Författare :Jaime Rodrigo Navarro; Sergei Popov; Gunnar Jacobsen; Richard Schatz; Xiaodan Pang; Oskars Ozolins; Gabriella Bosco; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; optical communications; carrier phase recovery; blind phase search; circular quadrature amplitude modulation; CmQAM; coherent optical communications; digital signal processing; carrier phase estimation; equalization enhanced phase noise; EEPN; Telecommunication; Telekommunikation;

   Sammanfattning : Coherent detection together with multilevel modulation formats has the potential to significantly increase the capacity of existing optical communication systems at no extra cost in signal bandwidth. However, these modulation formats are more susceptible to the impact of different noise sources and distortions as the distance between its constellation points in the complex plane reduces with the modulation index. LÄS MER

7. 5. Passive Optical Top-of-Rack Interconnect for Data Center Networks

   Författare :Yuxin Cheng; Jiajia Chen; Lena Wosinska; Matteo Fiorani; Qiong Zhang; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Optical communications; data center interconnects; MAC protocol; dynamic bandwidth allocation.; Informations- och kommunikationsteknik; Information and Communication Technology;

   Sammanfattning : Optical networks offering ultra-high capacity and low energy consumption per bit are considered as a good option to handle the rapidly growing traffic volume inside data center (DCs). However, most of the optical interconnect architectures proposed for DCs so far are mainly focused on the aggregation/core tiers of the data center networks (DCNs), while relying on the conventional top-of-rack (ToR) electronic packet switches (EPS) in the access tier. LÄS MER