Filetype
Vehicle-to-Vehicle (V2V) communication is an en-abler for improved traffic safety and congestion control. As for any wireless system the ultimate performance limit is determined by the propagation channel. A particular point of interest is the shadowing effect of large vehicles such as trucks and buses, as this might affect the communication range significantly. In this paper we present measuremen
An L1 adaptive controller of piecewise constant type has been applied to a fighter aircraft by augmenting it to a linear state-feedback controller. Angle of attack and sideslip as well as velocity vector roll rate is demanded and controlled. It is relatively easy to design a controller augmentation this way; few parameters need to be tuned. To design an L1-controller for roll/pitch/yaw-motion of a
We give a procedure to find good convolutional codes for use with iterative decoding (turbo equalization) of the coded AWGN intersymbol interference (ISI) channel. The method is based on the input-output bit error rate characteristic of the convolutional BCJR module in the iterative decoder, in combination with the code minimum distance. Both are essential to find best codes. Best feedforward and
Communication is essential for software development as its efficiency throughout the entire project life-cycle is a key factor in developing and releasing successful software products to the market. This paper reports on findings from an explanatory case study aiming at a deeper understanding of the causes and effects of communication gaps in a large-scale industrial set up. Based on an assumption
This paper presents a highly linear radio frequency receiver front-end with on-chip balun for cellular application at 2GHz in 65nm CMOS technology. Based on direct conversion architecture, the implemented front-end comprises a customized on-chip balun for single-ended to differential signal conversion, a differential common-gate low noise amplifier and voltage mode quadrature passive mixer. The si
To fulfill increasing requirements in the manufacturing sector, companies are faced with several challenges. Three major challenges have been identified regarding time-to-market, vertical feedback loops and level of automation. Grafchart, a graphical language aimed for supervisory control applications, can be used from the process-planning phase, through the implementation phase and all the way to
We have previously shown how it is possible to lower accident risk levels while at the same time increasing traffic flows with the aid of vehicular ad-hoc networks. In this paper, we extend the online traffic accident risk mitigation sys- tem to include link choice. We develop an algorithm that allows vehicles to choose road links that provide the current maximal utility, based on information rece
Coordinating a software project across distances is challenging. Even without geographical and time zone distances, other distances within a project can cause communication gaps. For example, organisational and cognitive distances between product owners and development-near roles such as developers and testers can lead to weak alignment of the software and the business requirements. Applying good
When a feedback controller is implemented in a networked embedded system, the computations and communications induce delays and jitter, which may destabilize the control loop. The majority of previous work on analysis of control loops with time-varying delays has focused on output (actuation) jitter. In many embedded systems, input (sampling) jitter is also an issue. In this paper, we analyze the
We have implemented a prototype editor for a visual language where the semantics depends on layout. A high-level abstract syntax is defined, where these semantics can be captured without the need for storing concrete graphical coordinates. The model implementation is done in JastAdd, a metacompilation tool based on reference attribute grammars. This gives a modular architecture where the core comp
Abstract in Undetermined The 60 GHz band is very prominsing for high data rate (>1 Gb/s) wireless systems operating at short ranges. However, due to the short wavelengths in this frequency band, the shadowing effects cuased by human bodies and furniture are severe and needs to be modeled properly. In this paper, we present an experimental, measurement-based characterization of the reflection and s
Synthesis of case studies is different from synthesis of purely quantitative studies, for example, in that sampling and analysis in primary studies have been carried out differently, and that primary results are of a different nature. The objective of this research is to identify what challenges should be considered when choosing and using a method for synthesis of case studies. We collected exper
When a mobile station moves along a trajectory, it will see different parts of the same scatterers or scatterer groups during its movement. In this paper, we present a new method to identify such physical clusters of scatterers, and the corresponding groups of multipath components (MPCs) interacting with those clusters, from measurements of channel impulse responses. The method is based on identif
In control theory there exist two convenient representations of a model, which are transfer functions and state-space matrices. However, structure in the transfer functions is not clearly seen in the state-space form, and on the other hand structure in the state-space form is not clearly seen in the transfer functions. The main reason for this is that Laplace transformation destroys most types of
This paper presents new versions of the McEliece PKC that use time-varying convolutional codes. In opposite to the choice of Goppa codes, the proposed construction uses large parts of randomly generated parity-checks, presumably making structured attacks more difficult. The drawback is that we have a small but nonzero probability of not being successful in decoding, in which case we need to ask fo
Autonomous vehicle functions in safety-critical situations show promise in reducing the risk and saving lives in accidents compared to existing safety systems. Consequently, it is from many perspectives advantageous to be able to quantify the potential benefits of new autonomous systems for vehicle maneuvers at-the-limit of tire friction. Here, to estimate the potential in terms of saved lives and
