Daniel Catrein

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Accurate power control is an essential requirement in the design of cellular code-division multiple-access (CDMA) systems. In this paper, we contribute three main themes to the power control problem. First, we derive an efficient algorithm for computing minimal power levels for large-scale networks within seconds. Nice and intuitive conditions for the(More)
Slow fading or shadowing on a wireless channel is commonly modeled by stochastically independent, log-normally distributed random variables. However, as slow fading is caused by buildings and large size obstacles, spatial correlations occur. In this paper, Gaussian random fields are used as a model for correlated slow fading in urban environments. An(More)
Ubiquitous sensing environments such as sensor networks collect large amounts of data. This data volume is destined to grow even further with the vision of the Internet of Things. Cloud computing promises to elastically store and process such sensor data. As an additional benefit, storage and processing in the Cloud enables the efficient aggregation and(More)
Today mobile TV services in cellular spectrum are delivered over unicast radio bearers as offered by 3G technologies like WCDMA and HSDPA. Since unicast transmission does not scale very well if mobile TV becomes a true mass service, 3GPP has defined a broadcast extension for UMTS, called Multimedia Broadcast Multicast Service (MBMS). MBMS introduces radio(More)
Dynamic adaptive HTTP streaming (DASH) is a new concept for video streaming using consecutive downloads of short video segments. 3GPP has developed the basic DASH standard which is further extended by the Open IPTV Forum (OIPF) and MPEG. In all versions available to date, only very simple content protection use cases are enabled. Extensions are needed to(More)
Power control is an essential feature of code division multiple access (CDMA) systems to guaranty quality of transmission and maximize network capacity. In this paper, we introduce a fast method for computing the minimal power assignment even for huge numbers of mobiles. Its complexity mainly depends on the number of base stations in the network. This type(More)
This paper is concerned with linear multiuser receivers for code division multiple access (CDMA). Mainly three are of practical relevance: the matched filter (MF), the successive interference cancellation (SIC) and the minimum mean squared error (MMSE) receiver. For the first time, an explicit representation of the signal-to-interference-plus-noise (SINR)(More)