Sökning: "Pico"

Visar resultat 16 - 20 av 24 avhandlingar innehållade ordet Pico.

1. 16. Terahertz spin dynamics in metallic thin film ferromagnets

   Författare :Kumar Neeraj; Stefano Bonetti; Andreas Rydh; Michael Farle; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Terahertz; ultrafast magnetism; spin dynamics; spin nutation; magnetization switching; fysik; Physics;

   Sammanfattning : The past two decades have witnessed an increasing interest in understanding and controlling materials at the pico- and femtosecond time scales, the so-called ultrafast regime. Among the broad field of condensed matter physics, magnetism and magnetic materials have attracted much interest both from a fundamental and an applied perspective. LÄS MER

3. 17. Deployment cost efficiency in broadband delivery with fixed wireless relays

   Författare :Bogdan Timus; Jens Zander; Claes Beckman; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Telecommunication; Telekommunikation;

   Sammanfattning : Although radio repeaters and wireless routers are commonly used, relaying techniques have received a lot of attention in academic publications the last decade. Most of the techniques proposed in the literature are based on relaying terminals. LÄS MER

4. 18. Radio Resource Allocation and Utilization in Multiple Radio Access Networks

   Författare :Georgios Koudouridis; Gunnar Karlsson; Frank H. P. Fitzek; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : Meeting in a sustainable way the demands of an unprecedented explosive growth in the number of connected devices and mobile data traffic, next-generation mobile networks are expected to make flexible use of spectrum and provide higher capacity by a denser deployment of radio access network infrastructure. In addition, the allocation and the utilisation of radio access resources should improve spectrum usage efficiency and keep energy consumption low, implying the capability to effectively exploit the denser deployment of radio accesses and the co-existence of radio accesses belonging to one or multiple radio access technologies. LÄS MER

5. 19. Study of Multi-Radio Transmission Diversity in Heterogeneous Access Networks

   Författare :Georgios Koudouridis; Gunnar Karlsson; Cigdem Sengul; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : With the advent of multi-radio access (MRA), an integration of differentradio access technologies (RATs) into a heterogeneous radio access network(RAN) becomes feasible. Such integration allows a user to be at any instantof time served by one or multiple radio accesses (RAs) concurrently, where anRA constitutes an independent radio resource, such as a carrier or a channel,implemented by a single RAT. LÄS MER

7. 20. Nonlinear optics in KTiOPO4 for spectral management of ultra-short pulses in the near- and mid-IR

   Författare :Anne-Lise Viotti; Valdas Pasiskevicius; Fredrik Laurell; Paulina Kuo; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Nonlinear optics; Ferroelectrics; Fysik; Physics;

   Sammanfattning : This thesis explores the possibilities of controlling nonlinear optical interactions in ferroelectric materials for bandwidth tailoring of ultrashort pulses in the pico- and femto-second range. The control is achieved through quasi-phase matching, which is based on alternating the material’s spontaneous polarization into different domains. LÄS MER