Search for dissertations about: "signal-to-noise ratio SNR"

Showing result 16 - 20 of 71 swedish dissertations containing the words signal-to-noise ratio SNR.

2. 16. Laboratory x-ray fluorescence tomography

   Author : Jakob C. Larsson; Hans Hertz; Anna Burvall; Ulrich Vogt; Norbert Pelc; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; x-ray; fluorescence; x-ray fluorescence; nanoparticle; xrf; xfct; tomography; Fysik; Physics;

   Abstract : X-ray fluorescence (XRF) tomography is an emerging bio-imaging modality with potential for high-resolution molecular imaging in 3D. In this technique the fluorescence signal from targeted nanoparticles (NPs) is measured, providing information about the spatial distribution and concentration of the NPs inside the object. READ MORE

4. 17. Channel Estimation for Amplify and Forward Relay Networks

   Author : Panagiota Lioliou; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; channel estimation; relay networks; Multiple-input-multiple-output MIMO ; Cramer-Rao Lower Bound CRB .; least squares LS ;

   Abstract : The use of intermediate-relaying nodes has been identified as a promising technique for enhancing coverage and combating the impairments of Multiple-Input-Multiple-Output (MIMO) wireless channels. The main ideais to introduce relays that forward the data to the destination which isotherwise out of the reach of the source. READ MORE

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

   Author : Samuel L I Olsson; Chalmers tekniska högskola; []
   Keywords : 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;

   Abstract : 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. READ MORE

6. 19. Towards Practical Implementation of Phase-Sensitive Amplifier Based Transmission Systems

   Author : Samuel L I Olsson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; phase-sensitive amplification; four-wave mixing; nonlinear optical signal processing; optical injection locking; fiber nonlinearities; fiber optic parametric amplification;

   Abstract : All commercially available optical amplifiers are so-called phase-insensitive amplifiers (PIAs) which degrade the signal-to-noise ratio (SNR) through the amplification process. This kind of amplifier has a quantum limited noise figure (NF) of 3 dB. READ MORE

7. 20. Adaptive MIMO Systems with Channel State Information at Transmitter

   Author : Jinliang Huang; Svante Signell; Øien Geir; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; adaptive modulation; adaptive power allocation; average spectral efficiency; MIMO; BER.; Telecommunication; Telekommunikation;

   Abstract :  This dissertation presents adaptation techniques that can achieve high spectral efficiency for single user multiple-input multiple-output (MIMO) systems. Two types of adaptation techniques, adaptive modulation and adaptive powe allocation, are employed to adapt the rate and the transmit power to fading channels. READ MORE