Sökning: "spatial division multiplexing"

Visar resultat 1 - 5 av 15 avhandlingar innehållade orden spatial division multiplexing.

1. 1. Power Consumption and Joint Signal Processing in Fiber-Optical Communication

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

   Sammanfattning : The power consumption of coherent fiber-optical communication systems is becoming increasingly important, for both environmental and economic 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. LÄS MER

3. 2. VCSEL and Integration Techniques for Wavelength-Multiplexed Optical Interconnects

   Författare :Mehdi Jahed; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wavelength setting; optical interconnects; mode control; vertical-cavity surface-emitting laser; flip-chip integration; wavelength-division-multiplexing; silicon photonics;

   Sammanfattning : GaAs-based vertical-cavity surface-emitting lasers (VCSELs) are dominating short-reach optical interconnects (OIs) due to their high modulation speed, low power consumption, circular output beam and low fabrication cost. Such OIs provide the high bandwidth connectivity needed for interconnecting servers and switches in data centers. LÄS MER

4. 3. Baseband Processing for 5G and Beyond: Algorithms, VLSI Architectures, and Co-design

   Författare :Mojtaba Mahdavi; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; VLSI Implementation; Hardware architectures; ASIC implementation; FPGA implementation; CMOS Technology; Baseband Processing; Massive MIMO; 5G New Radio; Beyond 5G; Co-Design; FFT processor; OFDM modulation; wireless communications; Massive MIMO Detection; Angular domain processing; Zero forcing; Systolic array; Non-linear detector; Channel Sparsity; Channel compression; Linear detector; Channel coding; Spatial coupling; Turbo-like codes; Spatially coupled serially concatenated codes; Threshold analysis; Decoder architecture; BCJR algorithm; MAP algorithm; Coupling memory; Window decoding; Complexity analysis; Performance Evaluation; Throughput; Decoding Latency; Silicon area; Design tradeoffs; Interleaver architecture; Memory requirements; Matrix multiplication; Channel state information CSI ; Cholesky decomposition; Tanner graph; Trellis codes; Convolutional encoder; Code design; Puncturing; Reordering circuit; wireless communication system; digital electronic;

   Sammanfattning : In recent years the number of connected devices and the demand for high data-rates have been significantly increased. This enormous growth is more pronounced by the introduction of the Internet of things (IoT) in which several devices are interconnected to exchange data for various applications like smart homes and smart cities. LÄS MER

5. 4. Optimization, Design, and Analysis of Flexible-Grid Optical Networks with Physical-Layer Constraints

   Författare :Li Yan; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; GN model; optimization; resource allocation; Flexible-grid optical network; heuristic algorithm; DCNs; regenerator location;

   Sammanfattning : The theme of this thesis is the optimization, design, and analysis of flexible-grid optical networks that are constrained by physical-layer impairments (PLIs). We consider three flexible-grid network scenarios. LÄS MER

7. 5. Adaptation in multiple input multiple output systems with channel state information at transmitter

   Författare :Jinliang Huang; Svante Signell; Anders Ahlén; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MIMO; adaptive modulation; power allocation; spectral efficiency; CSI; Electrical engineering; Elektroteknik;

   Sammanfattning : This thesis comprises two parts: the first part presents channel-adaptive techniques to achieve high spectral efficiency in a single user multiple-input multiple-output (MIMO) system; the second part exhibits a programmable and reconfigurable software-defined-radio orkbench(SDR-WB) in the Matlab/Octave environment that accommodates a variety of wireless applications. In an attempt to achieve high spectral efficiency, an adaptive modulation technique is applied at the transmitter to vary the data rate depending on the channel state information (CSI). LÄS MER