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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
In this paper, we investigate the impact of spatial coupling on the thresholds of turbo-like codes. Parallel concatenated and serially concatenated convolutional codes as well as braided convolutional codes (BCCs) are compared by means of an exact density evolution (DE) analysis for the binary erasure channel (BEC). We propose two extensions of the original BCC ensemble to improve its threshold an
A compact dual-element antenna suitable for ultrawideband (UWB) MIMO operation is proposed in this work. The size of the antenna is 25 mm by 40 mm and it covers the lower UWB band of 3.15-5.15 GHz. Apart from the inherent wideband isolation obtained through the different angle and polarization characteristics in the radiation patterns of the individual elements, the gap between the two antenna ele
Background: The fix-cache approach to regression test selection was proposed to identify the most fault-prone files and corresponding test cases through analysis of fixed defect reports. Aim: The study aims at evaluating the efficiency of this approach, compared to the previous regression test selection strategy in a major corporation, developing embedded systems. Method: We launched a post-hoc
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
Abstract in UndeterminedVery large MIMO is a technique that potentially can offer large network capacities in multi-user scenarios where the users are equipped only with single antennas. In this paper we are investigating channel properties for a realistic, though somewhat extreme, outdoor base station scenario using a large array. We present measurement results using a 128 element linear array ba
The traditional routing protocols used in wireless mesh networks like AODV are not very efficient since the number of hops to a destination is mainly considered as the routing metric. This may lead to shorter paths; however, the throughput can decrease when traffic is routed through those paths. Various contributions have proposed different metrics or completely different routing algorithms. Never
Spatially coupled regular LDPC code ensembles have outstanding performance with belief propagation decoding and can perform close to the Shannon limit. In this paper we investigate the suitability of coupled regular LDPC code ensembles with respect to rate-flexibility. Regular ensembles with good performance and low complexity exist for a variety of specific code rates. On the other hand it can be
With increasing usage of the Internet, energy consumption of network equipment has become a crucial challenge from both an economic and an environmental point of view. This paper combines users’ behavior of accessing the network with energy saving algorithms for energy-aware network equipment, and investigates potential energy savings in the access network. The study is based on a set of traffic d
In this paper we evaluate the use of parallel interleavers for user separation in coded IDMA systems. The parallel interleavers have previously been evaluated for uncoded systems, and we here present extended results for the coded case. The new results are important for real systems, as they will most likely use performance enhancing channel coding. The parallel interleavers are designed to remove
Context: Systems of systems (SoS) are highly complex and are integrated on multiple levels (unit, component, system, system of systems). Many of the characteristics of SoS (such as operational and managerial independence, integration of system into system of systems, SoS comprised of complex systems) make their development and testing challenging. Contribution: This paper provides an understanding
We consider the problem of detecting exploits based on return-oriented programming. In contrast to previous works we investigate to which extent we can detect ROP payloads by only analysing streaming data, i.e., we do not assume any modifications to the target machine, its kernel or its libraries. Neither do we attempt to execute any potentially malicious code in order to determine if it is an att
We present a model for supporting scoping decisions that is based on an analysis of the ROI for a given feature. Employing a ROI threshold value for making scoping decisions, the utility of the model was investigated using data from a single large project and identified a group of outlying features responsible for a disproportionate wasted investment. These initial results are promising and indica
An M-BCJR algorithm is proposed and tested over an AWGN channel with moderate to very intense intersymbol interference (ISI). Two M-BCJR applications are evaluated, simple detection over the ISI channel and turbo equalization. The signaling is binary faster than Nyquist linear modulation. The ISI models tested correspond to transmission of increasingly many bits/Hz-s with a fixed signal spectra; t
A differential LNA using capacitive shunt feedback is demonstrated in 65nm CMOS. The capacitive shunt feedback structure gives a wideband input matching, S11 <;-17 dB from 500MHz - 1 GHz for low band and S11 <;-20 dB from 1.1 GHz - 2.3GHz for high band. The NF for the complete receiver chain in low band and high band was measured to 3.3 dB and 3.9 dB, respectively. The 1-dB compression point with
The goal of the paper is to present a distributed scheme to resolving a single path routing problem in multidomain networks. The global problem is formulated as a mixed-integer program (MIP) and approached by means of branch-and-price (B&P). Problems associated with a B&P tree nodes are decomposed using the Dantzig-Wolfe method to a set of domain subproblems coordinated by a single master
We consider the problem of providing trusted computing functionality in high availability systems. We consider the case where data is required to be encrypted with a TPM protected key. For redundancy, and to facilitate high availability, the same TPM key is stored in multiple computational units, each one ready to take over if the main unit breaks down. This requires the TPM key to be migratable.
In large software organizations with a product line development approach, system test planning and scope selection is a complex tasks for which tool support is needed. Due to repeated testing: across different testing levels, over time (test for regression) as well as of different variants, the risk of double testing is large as well as the risk of overlooking important tests, hidden by the huge a
