Search results for "langaton tiedonsiirto"

Quality of service and pricing in future multiple service class networks

2006

Ari Viinikainen tutki väitöskirjassaan tietoliikenneverkkojen resurssien jakoa hinnoittelun ja palvelun laadun avulla sekä kiinteissä että langattomissa tietoliikenneverkoissa. Aihe on ajankohtainen, sillä vaikka verkkojen tiedonsiirtokapasiteetti kasvaa, ei kaikille sovelluksille voida taata niiden vaatimaa tiedonsiirtopalvelun laatua. Esimerkiksi videoneuvottelujen laadun kannalta olennaisia ovat mahdollisimman pieni viive, vähäinen viiveen vaihtelu ja suuri tiedonsiirtokapasiteetti. Viinikainen esittelee työssään useita viiveen tai tiedonsiirtonopeuden takaavia algoritmeja, joilla reitittimiin saapuvaa dataa voidaan priorisoida. Algoritmien toiminta perustuu siirrettävän tiedon erilaisee…

An Analysis of the Flow-Based Fast Handover Method For Mobile IPv6 Network

2006

Mobile IPv6 has been proposed by the IETF (Internet Engineering Task Force) to be the solution to mobility management in IPv6 network. The work is now culminating to a standard status. But, one problem still remaining is the length of the handover time, which might cause packet loss. Thus the handover time should be as short as possible. Especially the real-time traffic suffers from packet loss. Earlier we have introduced a new method for faster handover process in Mobile IPv6 network called the Flow-based Fast Handover Method for Mobile IPv6 (FFHMIPv6). FFHMIPv6 uses the flow state information stored in the routers for the fast redirection of the flow. In this paper we compare the proposed…

Cooperative spectrum sensing schemes for future dynamic spectrum access infrastructures

2016

Joint Subcarrier and Phase Shifts Optimization for RIS-aided Localization-Communication System

2022

Joint localization and communication systems have drawn significant attention due to their high resource utilization. In this paper, we consider a reconfigurable intelligent surface (RIS)-aided simultaneously localization and communication system. We first determine the sum squared position error bound (SPEB) as the localization accuracy metric for the presented localization-communication system. Then, a joint RIS discrete phase shifts design and subcarrier assignment problem is formulated to minimize the SPEB while guaranteeing each user’s achievable data rate requirement. For the presented non-convex mixed-integer problem, we propose an iterative algorithm to obtain a suboptimal solution …

Multi-hop D2D Communications with Network Coding : From A Performance Perspective

2019

Multi-hop device-to-device (D2D) communications play an important role in expanding D2D coverage. In this paper, we study a relay-based and network-coding-assisted (in particular, XOR coding) multi-hop D2D communication system. In the system, toward jointly considering the impact of interference and network traffic conditions on the quality of D2D communications, various channel fading models and traffic models are investigated, and the packet loss probability of D2D links is meticulously computed using these models. With the packet loss probability of D2D links, the general closed-form expressions of end-to-end packet loss probability (E2EPLP) of the system with the presence (or absence) o…

Energy Efficient Optimization for Wireless Virtualized Small Cell Networks With Large-Scale Multiple Antenna

2017

Wireless network virtualization is envisioned as a promising framework to provide efficient and customized services for next-generation wireless networks. In wireless virtualized networks (WVNs), limited radio resources are shared among different services providers for providing services to different users with heterogeneous demands. In this paper, we propose a resource allocation scheme for an orthogonal frequency division multiplexing-based WVN, where one small cell base station equipped with a large number of antennas serves the users with different service requirements. In particular, with the objective to obtain the energy efficiency in the uplink, a joint power, subcarrier, and antenn…

Service-Oriented Wireless Virtualized Networks: An Intelligent Resource Management Approach

2022

Resource Allocation and Computation Offloading for Wireless Powered Mobile Edge Computing

2022

In this paper, we investigate a resource allocation and computation offloading problem in a heterogeneous mobile edge computing (MEC) system. In the considered system, a wireless power transfer (WPT) base station (BS) with an MEC sever is able to deliver wireless energy to the mobile devices (MDs), and the MDs can utilize the harvested energy for local computing or task offloading to the WPT BS or a Macro BS (MBS) with a stronger computing server. In particular, we consider that the WPT BS can utilize full- or half-duplex wireless energy transmission mode to empower the MDs. The aim of this work focuses on optimizing the offloading decision, full/half-duplex energy harvesting mode and energ…