Sökning: "White noise"

Visar resultat 1 - 5 av 80 avhandlingar innehållade orden White noise.

  1. 1. Multi-Gigabaud Millimeter-Wave Communication - Challenges and Solutions

    Detta är en avhandling från ; Chalmers tekniska högskola; Gothenburg

    Författare :Jingjing Chen; [2017]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; phase noise; high-order modulation; 5G; multi-gigabaud; PAM-4; high data rate; white noise; multi-gigabit; phase noise mitigation; 64-QAM; mobile backhaul; VCSEL driver; Frequency multiplier; modem; high frequency oscillator; multiplicative noise; power detector; fronthaul; millimeter-wave communication;

    Sammanfattning : A major challenge in future mobile networks is to overcome the capacity barrier in wireless communication. Utilizing large bandwidth at higher frequencies is key to enabling capacity upgrade for next generation mobile networks (5G). LÄS MER

  2. 2. Modeling and Estimation of Phase Noise in Oscillators with Colored Noise Sources

    Detta är en avhandling från ; Chalmers tekniska högskola; Gothenburg

    Författare :M Reza Khanzadi; [2013]
    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; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Phase Noise Model; Bayesian Cramer-Rao Bound; Voltage-controlled Oscillator; Extended Kalman Filter Smoother; Maximum a Posteriori Estimator; Colored Phase Noise; Oscillator Phase Noise; Phase-Locked Loop; Mean Square Error.;

    Sammanfattning : The continuous increase in demand for higher data rates due to applications with massive number of users motivates the design of faster and more spectrum efficient communication systems. In theory, the current communication systems must be able to operate close to Shannon capacity bounds. LÄS MER

  3. 3. Frequency Noise in Coherent Optical Systems: Impact and Mitigation Methods

    Detta är en avhandling från Stockholm, Sweden : KTH Royal Institute of Technology

    Författare :Aditya Kakkar; KTH.; [2017]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Equalization enhanced phase noise; frequency noise; coherent optical communications; carrier phase recovery; carrier phase estimation; circular quadrature amplitude modulation; EEPN; CmQAM; blind phase search; phase noise;

    Sammanfattning : The increase in capacity demand along with the advancement in digital signal processing (DSP) have recently revived the interest in coherent optical communications and led to its commercialization. However, design and development of robust DSP algorithms for example for carrier phase recovery (CPR) becomes complex as we opt for high order modulation formats such as 16QAM and beyond. LÄS MER

  4. 4. Risk of hearing loss from combined exposure to hand-arm vibrations and noise

    Detta är en avhandling från Umeå : Umeå universitet

    Författare :Hans Pettersson; Umeå universitet.; [2013]
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Hearing loss; noise; hand-arm vibration; combined exposure; vibration induced white fingers; Raynaud s phenomenon; Occupational and Environmental Medicine; arbets- och miljömedicin;

    Sammanfattning : Hearing loss from noise exposure is one of the most common occupational injuries, and exposure to vibrations may increase the risk of noise-induced hearing loss. Earlier cross-sectional and longitudinal studies found an increased risk of noise-induced hearing loss among workers with vibration-induced white fingers (VWF) symptoms compared to workers without such symptoms. LÄS MER

  5. 5. Noise improves cognitive performance in children with dysfunctional neurotransmission

    Detta är en avhandling från Stockholm : Psykologiska institutionen

    Författare :Göran Söderlund; Stockholms universitet.; [2007]
    Nyckelord :SAMHÄLLSVETENSKAP; SOCIAL SCIENCES; ADHD; noise; stochastic resonance; dopamine; episodic memory; model; brain arousal; SPT; cognitive performance; children; SOCIAL SCIENCES Social sciences Psychology; SAMHÄLLSVETENSKAP Socialvetenskap Psykologi; psykologi; Psychology;

    Sammanfattning : Research on children with Attention Deficit Hyperactivity Disorder (ADHD) has shown that they are extremely sensitive to distraction from external stimuli that lead to poor cognitive performance. This thesis shows that cognitive performance can be improved if this external stimulus is smooth and continuous (e.g. auditory white noise). LÄS MER