Sökning: "quadrature amplitude modulation"

Visar resultat 16 - 20 av 26 avhandlingar innehållade orden quadrature amplitude modulation.

  1. 16. Multidimensional Constellation Shaping for Coherent Optical Communication Systems

    Författare :Ali Mirani; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; lattice-based constellations; geometric shaping; probabilistic shaping; multidimensional modulation format; Voronoi constellation; constellation shaping; optical communications; coherent receiver;

    Sammanfattning : To overcome the increasing demands for Internet traffic, exploiting the available degrees of freedom in optical communication systems is necessary. In this thesis, we study how constellation shaping can be achieved in various dimensions and how various shaping schemes affect the whole performance in real systems. LÄS MER

  3. 17. Multi-Gigabaud Solutions for Millimeter-wave Communication

    Författare :Sining An; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Millimeter-wave communication; power amplifier; mobile network; power combining; outphasing; high order modulation; DQPSK; modem; pilot; 16-QAM; non-linear distortion; E-band; high data rate; carrier recovery;

    Sammanfattning : With the growing number of mobile network and internet services subscriptions, faster communication will provide a better experience for users. In the next generation mobile network, the fifth generation (5G), communication data rate will achieve several Gigabits per second with ultra-low latency. LÄS MER

  4. 18. Phase-Sensitive Parametric Signal Processing in Optical Communications

    Författare :Abel Lorences Riesgo; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : This thesis covers the analysis of several schemes for parametric processing in fiberoptic communication systems, focusing mainly on phase-sensitive processing. Vector phase-sensitive amplifiers are characterized and phase regeneration of a dualpolarization (DP)-binary phase-shift keying signal (BPSK) signal is experimentally demonstrated. LÄS MER

  5. 19. Optical Transmission Systems Based on Phase-Sensitive Amplifiers

    Författare :Samuel L I Olsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; optical injection locking; fiber nonlinearities; optical fiber communication; fiber nonlinearity mitigation; four-wave mixing; fiber optic parametric amplification; low-noise amplification; phase-sensitive amplification; fibre optics;

    Sammanfattning : The capacity and reach of today's long-haul fiber optical communication systems is limited by amplifier noise and fiber nonlinearities. Conventional, phase-insensitiveamplifiers (PIAs), have a quantum limited noise figure (NF) of 3 dB at high gain, meaning that with a shot-noise limited input signal the signal-to-noise ratio (SNR)is degraded by at least 3 dB. LÄS MER

  7. 20. Coherent Optical Transmission Systems : Performance and Coding Aspects

    Författare :Miu Yoong Leong; Sergei Popov; Gunnar Jacobsen; Enrico Forestieri; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Since the invention of fiber-optic systems in the 1970s, user demand has driven innovation forward, and each new generation of products has achieved higher data rates than its predecessor. Today, the most promising approach for further increasing data rates is coherent transmission with multi-level modulation and digital signal processing (DSP). LÄS MER