Sökning: "Jan-Åke Larsson"
Visar resultat 1 - 5 av 11 avhandlingar innehållade orden Jan-Åke Larsson.
1. Spectrum Sensing Algorithms Based on Second-Order Statistics
Sammanfattning : Cognitive radio is a new concept of reusing spectrum in an opportunistic manner. Cognitive radio is motivated by recent measurements of spectrum utilization, showing unused resources in frequency, time and space. Introducing cognitive radios in a primary network inevitably creates increased interference to the primary users. LÄS MER
2. Quantum paradoxes, probability theory, and change of ensemble
Sammanfattning : In this thesis, the question "What kind of models can be used to describe microcosmos?" will be discussed. Being difficult and very large in scope, the question has here been restricted to whether or not Local Realistic models can be used to describe Quantum-Mechanical processes, one of a collection of questions often referred to as Quantum Paradoxes. LÄS MER
3. Authentication in Quantum Key Distribution : Security Proof and Universal Hash Functions
Sammanfattning : Quantum Key Distribution (QKD) is a secret key agreement technique that consists of two parts: quantum transmission and measurement on a quantum channel, and classical post-processing on a public communication channel. It enjoys provable unconditional security provided that the public communication channel is immutable. LÄS MER
4. Weaknesses of Authentication in Quantum Cryptography and Strongly Universal Hash Functions
Sammanfattning : Authentication is an indispensable part of Quantum Cryptography, which is an unconditionally secure key distribution technique based on the laws of nature. Without proper authentication, Quantum Cryptography is vulnerable to “man-in-the-middle” attacks. LÄS MER
5. A Few-Mode-Fiber Platform for Quantum Communication Applications
Sammanfattning : Society as we know it today would not have been possible without the explosive and astonishing development of telecommunications systems, and optical fibers have been one of the pillars of these technologies.Despite the enormous amount of data being transmitted over optical networks today, the trend is that the demand for higher bandwidths will also increase. LÄS MER