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This paper assumes the availability of a very fast higher-dimensional rasterizer in future graphics processors. Working in up to five dimensions, i.e., adding time and lens parameters, it is well-known that this can be used to render scenes with both motion blur and depth of field. Our hypothesis is that such a rasterizer can also be used as a flexible tool for other, less conventional, usage area

There has been extensive research about single link multiple-input multiple-output (MIMO) channels, both simulated and measured, but only few studies have targeted multilink analysis with measured channel data. Hence, in this paper, we analyze the influence of spatial separation of user terminals and the human shadowing effect on the MIMO capacity and to the signal to interference ratio (SIR) in a

Software development organizations are continuously looking for better ways to manage their projects. An emerging approach to achieve this is Inner Source, which refers to the adoption of Open Source development practices within the confines of an organization. With an Inner Source approach, individuals, teams, and departments within an organization can start software projects, very similar to the

Many combinatorial optimization problems lend themselves to be modeled as distributed constraint optimization problems (DisCOP). Problems such as job shop scheduling have an intuitive matching between agents and machines. In distributed constraint problems, agents control variables and are connected via constraints. We have equipped these agents with a full constraint solver. This makes it possibl

Embedded DSP computing is currently shifting towards manycore architectures in order to cope with the ever growing computational demands. Actor based dataflow languages are being considered as a programming model. In this paper we present a code generator for CAL, one such dataflow language. We propose to use a compilation tool with two intermediate representations. We start from a machine model o

Execution trace graph analysis of dataflow programs has been demonstrated to be an effective way for exploring and optimizing the design space of many core applications. In this work a novel transformation from the execution trace graph to an event driven linear system is proposed. It is also illustrated how the trace space of can be effectively reduced and well known system control techniques can

Cooperative content replication and request routing (C2R3) has emerged as a promising technique to enhance the efficiency of content delivery networks (CDN). Most existing approaches to C2R3 focus on efficient bandwidth usage and assume a hierarchical CDN architecture targeted towards the delivery of specific content types (e.g., video). Therefore, C2R3 problem of covering the broad range of conte

The design of a digital baseband for a low power wireless receiver in 65 nm CMOS is presented. It consists of decimation filtering, matched filters for data detection, and preamble based synchronization. The circuit was designed using low threshold devices in both low power (LP-LVT) and general-purpose (GP-LVT) domains. The fabricated circuits were functionally verified, and silicon measurements s

In this paper we present an analysis of the effects of antenna placement on the radio channel properties for Vehicle-to-Vehicle communications based on measurements performed in three different propagation scenarios; highway, urban and rural. Four omni-directional antennas were mounted at four different positions: roof, bumper, left-side mirror and inside windscreen of two standard station wagons

The ambitious goal of the upcoming IEEE 802.11ax (HEW) standard for wireless LANs (WLANs) to enhance throughput by four times (and beyond), compared with IEEE 802.11ac, demands a radical improvement of present medium access control (MAC) functionality. To this end, a promising paradigm would be a graceful migration towards new MAC protocols which incorporate higher certainty in their decisions. Ho

Video-on-Demand (VoD) and video sharing services account for a large percentage of the total downstream Internet traffic. In order to provide a better understanding of the load on these services, we analyze and model a workload trace from a VoD service provided by a major Swedish TV broadcaster. The trace contains over half a million requests generated by more than 20000 unique users. Among other

This paper presents a detailed description of a propagation channel measurement campaign performed in a warehouse environment and provide a comprehensive channel model for this environment. Using a vector network analyzer (VNA), we explored both Line-of-sight(LOS) and Non-Line-of-sight (NLOS) scenarios over a 2-8 GHz frequency range. We extracted both small-scale and large-scale channel parameters

Governmental organisations are becoming more critically dependant on IT systems such as communication systems or patient data systems, both for their everyday tasks and their role in crisis relief activities. Therefore it is important for the organisation to analyse the reliability of these systems as part of the organisation’s risk and vulnerability analysis process. This paper presents a practic

Low-density parity-check convolutional (LDPCC) codes, also known as spatially coupled LDPC codes, can be decoded using a message passing algorithm. In order to limit decoding latency and complexity, windowed decoding can be applied. Updates within the window can be performed either in parallel or serially. However, simulation results show that uniform updating schedules do not provide the expected

In this paper, we confirm that angle and polarization diversities are indeed the dominant diversity mechanisms of a recently proposed compact six-port MIMO antenna array, as it exhibits similar effective degree-of-freedom (EDOF) performance as that of the ideal array with co-located antenna elements evaluated in propagation scenarios with different angular spreads. Furthermore, the same approach c

We find good rate 2/3 and 3/4 convolutional codes for use with iterative decoding (turbo equalization) of coded intersymbol interference with AWGN. The method is based on the input-output bit error rate characteristic of the convolutional BCJR decoder module. An analysis leads to an equivalent minimum distance under the required intrinsic subtraction, which depends on free distance and an input-ou

The trade-off between throughput and memory constraints is a common design problem in embedded systems, and especially for streaming applications, where the memory in question usually occurs in the form of buffers for streams of data. This paper presents a methodology, based on the post-processing of dataflow execution traces, that enables designers to make principled choices in the design space f