Nokia

About: Nokia is a company organization based out in Espoo, Finland. It is known for research contribution in the topics: Signal & Mobile station. The organization has 16625 authors who have published 28347 publications receiving 695725 citations. The organization is also known as: Nokia Oyj & Oy Nokia Ab.

Interference-Aware Resource Allocation for Device-to-Device Radio Underlaying Cellular Networks

Abstract: Future cellular networks such as IMT-Advanced are expected to allow underlaying direct Device-to-Device (D2D) communication for spectrally efficient support of eg rich multimedia local services Enabling D2D links in a cellular network presents a challenge in radio resource management due to the potentially severe interference it may cause to the cellular network We propose a practical and efficient scheme for generating local awareness of the interference between the cellular and D2D terminals at the base station, which then exploits the multiuser diversity inherent in the cellular network to minimize the interference System simulations demonstrate that substantial gains in cellular and D2D performance can be obtained using the proposed scheme

DVB-H: Digital Broadcast Services to Handheld Devices

Abstract: This paper gives a brief review of the new Digital Video Broadcasting-Handheld(DVB-H) standard. This is based on the earlier standard DVB-T, which is used for terrestrial digital TV broadcasting. The new extension brings features that make it possible to receive digital video broadcast type services in handheld, mobile terminals. The paper discusses the key technology elements-4K mode and in-depth interleavers, time slicing and additional forward error correction-in some detail. It also gives extensive range of performance results based on laboratory measurements and real field tests. Finally it presents viewpoints relevant for DVB-H network design and system use in general.

A time and frequency synchronization scheme for multiuser OFDM

Abstract: We present a multiuser synchronization scheme for tracking the mobile's uplink time and frequency offsets. It uses the redundancy introduced by the cyclic prefix and does not need additional pilots. We show performance results of an orthogonal frequency division multiplexing (OFDM)-based radio interface based on the universal mobile telecommunication system (UMTS) parameters. For a UMTS-typical mobile channel environment, the performance of a coherent system employing the scheme is virtually indistinguishable from the performance of a perfectly synchronized system. In a differentially modulated system, synchronization errors decrease the system performance by about 0.7 dB compared to a perfectly synchronized system.

Rate adaptation for adaptive HTTP streaming

Abstract: Recently, HTTP has been widely used for the delivery of real-time multimedia content over the Internet, such as in video streaming applications. To combat the varying network resources of the Internet, rate adaptation is used to adapt the transmission rate to the varying network capacity. A key research problem of rate adaptation is to identify network congestion early enough and to probe the spare network capacity. In adaptive HTTP streaming, this problem becomes challenging because of the difficulties in differentiating between the short-term throughput variations, incurred by the TCP congestion control, and the throughput changes due to more persistent bandwidth changes.In this paper, we propose a novel rate adaptation algorithm for adaptive HTTP streaming that detects bandwidth changes using a smoothed HTTP throughput measured based on the segment fetch time (SFT). The smoothed HTTP throughput instead of the instantaneous TCP transmission rate is used to determine if the bitrate of the current media matches the end-to-end network bandwidth capacity. Based on the smoothed throughput measurement, this paper presents a receiver-driven rate adaptation method for HTTP/TCP streaming that deploys a step-wise increase/ aggressive decrease method to switch up/down between the different representations of the content that are encoded at different bitrates. Our rate adaptation method does not require any transport layer information such as round trip time (RTT) and packet loss rates which are available at the TCP layer. Simulation results show that the proposed rate adaptation algorithm quickly adapts to match the end-to-end network capacity and also effectively controls buffer underflow and overflow.

Information retrieval system

Abstract: A method and devices for a mobile person's information retrieval where, when the person is moving, on coming closer to a point of destination, defined by him as being interesting, than a specified threshold separation, he will be informed of such a point of interest and, on request, additional data will be presented on it, such as driving instructions or a map. The person is also offered a button with which he can make a call to the phone number of the point of interest presented each time. The person can add by himself new points of interest and select from available points of interest individual or several points of interest on the basis of their class, such as, e.g. restaurants or service stations.