Birgitta Olin

Streaming applications over HSDPA in mixed service scenarios

High-speed downlink packet access (HSDPA) is included in release 5 of the WCDMA specifications to increase downlink capacity and bitrates. This paper considers performance aspects of streaming applications over HSDPA in a mixed streaming and best-effort service scenario. Different scheduling algorithms are evaluated with the aim of providing sufficient quality-of-service for streaming. The simulation results show that reasonable streaming performance can be achieved without service differentiation if a somewhat fair scheduler is used, and that a streaming-aware scheduler further can protect streaming quality-of-service in high load conditions.

A streaming video traffic model for the mobile access network

A model of streaming video traffic from a streaming server to an end user is proposed. It mimics the codec output (video frames) segmentation into RTP (real time protocol) packets, transmission from the streaming server and reception of packets by the end user. The intention is to use the model in the performance analysis of radio networks. The level of detail is chosen to support the performance analysis of the transport of RTP packets from server to user. The model is based on measurements of H.263 encoded video at various bitrates. The bitrates and the codec settings are chosen to be suitable for mobile access.

Using dedicated in-building systems to improve HSDPA indoor coverage and capacity

In WCDMA systems, in particular with the introduction of high-speed multimedia services, the demand for good indoor coverage will become important. Overlaying macro cells can provide a sufficient level of general indoor coverage for most of the cases. However, in order to be able to provide WCDMA indoor coverage and capacity within traffic hot spots, such as airports, shopping malls and large office buildings, the deployment of dedicated in-building systems may be required. In this paper, the gain of deploying dedicated in-building systems in terms of HSDPA indoor coverage and capacity is studied; first, with a simple analytical reasoning and after that, with advanced system simulations. The results show that the HSDPA performance can be improved considerably within the indoor hotspot area by deploying a dedicated in-building system. The results also demonstrate how a dedicated in-building system can off-load the overlaying macro cell, and as a result of that, improve the grade of service considerably for the co-existing non-HSDPA users.

Voice-over-IP-over-wireless

The IP-technology is gaining momentum and it seems inevitable that future wireless telephony services will be based on IP-technology. However, in order for this to become reality a number of issues must be solved. In this paper we present solutions-header compression and traffic classification-and figures indicating that for WCDMA, voice over IP can be competitive with traditional circuit switched speech services.

A novel approach to WCDMA radio network dimensioning

A novel dimensioning approach for WCDMA radio networks is suggested. It is derived to handle real-time services on dedicated channels, but can easily be augmented to include best-effort traffic on the high-speed downlink shared channel. The method facilitates calculation of transmit power distributions based on detailed link gain statistics, enabling fast, yet accurate, estimation of, e.g., network design and cost. It is shown that good agreement with detailed dynamic simulations can be achieved.

Self-optimizing antenna muting - energy consumption and user thoughput analysis

Energy consumption in mobile networks, e.g. 3G networks, may be a substantial part of an operators expenses. A large part of the total energy of the network is consumed by the radio access network. Today operators are saving energy by turning off carriers or cells during periods with low traffic by manually configuring on-off periods. At the same time, operators are seeking to increase cost efficiency through simplifying network management processes by means of automation. In this paper we address energy saving by introducing an approach that automatically and without operator involvement deactivates radio units during periods with low load. We demonstrate the benefits of antenna deactivation using a dynamic simulator and a realistic deployment based on a major Western European city. The results presented suggest that there is potential for significantly enhancing the energy efficiency in mobile networks by adaptive activation of radio units.