Berger S.,TU Dresden |
Danneberg M.,TU Dresden |
Zanier P.,Nokia Inc. |
Viering I.,Nomor Research |
Fettweis G.,TU Dresden
Eurasip Journal on Wireless Communications and Networking | Year: 2015
Despite the orthogonality of LTE’s uplink transmission, it can happen that signals which are received at the base station with low power are drown out by strong signals from other users. Reason is the limited quantization resolution of the base station’s analog-to-digital converter. Since this effect causes a quality of service degradation for users at the cell edge, the dynamic receive power range of uplink signals arriving at the base station should be upper limited. However, setting an adequate upper limit for the dynamic receive power range is not trivial since many effects, such as quantization noise, fast fading etc., decrease the dynamic range which the analog-to-digital converter can handle in theory. In this paper, we measure the maximal uplink dynamic receive power range, denoted as uplink dynamic range threshold, for our LTE-like measurement setup by monitoring the uplink bit-error-rate of a first user while decreasing its transmit power during the presence of a second adjacently scheduled user with fixed transmit power. As the measured threshold is 31.4±7.6 dB, we can conclude that a link-budget-based estimation of the dynamic receive power range, which has been published previously, is accurate since its result coincides with the measurement. © 2015, Berger et al.
Panzner B.,Nokia Inc. |
Pauli V.,Nomor Research |
Yu L.,Nomor Research |
Viering I.,Nomor Research
Proceedings of the International Symposium on Wireless Communication Systems | Year: 2016
Due to the availability of large contiguous bands in excess of several gigahertz in the millimeter wave spectrum, millimeter wave communications will play a key role in 5G - The next generation mobile networks. The applicability of simple air interfaces without the need for complex techniques for optimized spectrum utilization make mmW carrier frequencies a preferred solution to cope with the huge traffic demand. The smaller wavelength enables usage of large antenna arrays supporting strong beamforming gains that compensate for the higher path loss at mmW frequencies and thus allow for a deployment of cellular access networks in dense urban outdoor scenarios. This work focuses on a real-time software demo of a 5G mmW network in a Chicago model operating at 73GHz. The propagation effects and implemented channel model is based on measurements performed at 73GHz. The 5G demo illustrates the dynamic cell re-routing caused by terminal and scatterer mobility in a 3D view of the dense urban street scenario and computes all relevant key performance indicators derived using a detailed RRM model. The key feature of this 5G mmW demo is the modeling of inband wireless backhaul techniques to foster realistic deployments of mmW access nodes including inexpensive wireless backhaul links to the egress point(s) within the same band. © 2015 IEEE.
Stockhammer T.,Nomor Research |
Heiles J.,Nokia Inc. |
Luken J.,Nokia Inc.
Multimedia Tools and Applications | Year: 2011
IPTV services have been widely deployed by network operators around the world over the last years. However, real-time streaming of Linear TV and Video-on- Demand (VoD) offerings, especially in High Definition quality, still puts a high burden on the network and content servers concerning bandwidth, Quality-of-Service, processing performance and scalability if 100.000s of users have to be supported simultaneously. While multicast delivery can cope with some of these problems for Linear TV services, the unicast VoD services cannot take advantage of that and especially the request for ondemand content is expected to substantially grow in the future. With the introduction of Content Download Services (CDSs), operators have the option to provide IPTV services in innovative ways: They can provide high-quality video services to users with limited access bandwidth, offload the streaming request for blockbuster movies at peak times from the VoD servers or provided personalized advertisements for insertion into a live program event in advance to the users end device. The Digital Video Broadcast (DVB) Project has recently finalized its CDS specification within its IPTV specification efforts. DVB CDS supports push and pull delivery models with unicast, multicast and peer-to-peer distribution in order to enable various business models and use cases. In this work we introduce the specified technology and map it to example use cases and business models. © 2010 Springer Science+Business Media, LLC.
Gozalvez D.,Polytechnic University of Valencia |
Pauli V.,Nomor Research |
Moon S.,LG Corp |
Ko W.-S.,LG Corp
IEEE International Symposium on Broadband Multimedia Systems and Broadcasting, BMSB 2011 - Conference Programme | Year: 2011
This paper investigates the utilization of subcarrier diversity (SD) in modern broadcasting systems to achieve transmit diversity. SD takes advantage of orthogonal frequency-division multiplexing (OFDM) and robust forward error correction (FEC) to exploit the space diversity of multiple transmit antennas. In particular, we focus on a variant of SD that we call transmit antenna switching (TxAS) in which each antenna transmits only in one contiguous portion of the spectrum. This way, it is possible to achieve a higher diversity than single transmit antenna configurations with no significant increase in terms of complexity or pilot density. As a result, the utilization of TxAS can outperform more complex space-frequency block codes (SFBC) like Alamouti if the transmission of pilots is taken into account. We evaluate the performance of the proposed technique by means of physical layer simulations in the context of DVB-NGH (Digital Video Broadcasting - Next Generation Handheld), the future broadcasting DVB system for the provision of mobile services to handheld devices. © 2011 IEEE.
Stockhammer T.,Nomor Research |
2012 IEEE Visual Communications and Image Processing, VCIP 2012 | Year: 2012
This paper provides an overview on the challenges of mobile video streaming focusing on overload situations, variable bandwidth and power consumption issues. Dynamic Adaptive Streaming over HTTP (DASH) is introduced as an enabler to address a significant portion of these challenges. The applicability of the formats to 3G and 4G unicast distribution is provided. Also the applicability of DASH formats for multicast distribution in MBMS is shown. Finally, the usage of DASH in hybrid unicast/multicast is introduced to provide a flexible extension to support different business and delivery models. An outlook to ongoing and future work is provided. © 2012 IEEE.