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Path loss models are the most fundamental part of wireless propagation channel models. Path loss is typically modelled as a (single-slope or multi-slope) power-law dependency on distance plus a log-normally distributed shadowing attenuation. Determination of the parameters of this model is usually done by fitting the model to results from measurements or ray tracing. The authors show that the typi

We have previously presented Intent, a medium access control scheme for WLANs based on cooperative, distributed, non-binding frame scheduling. The main idea behind Intent is intention sharing - a mechanism that allows a node to be aware of transmissions previously scheduled by its neighbors. We now extend this scheme to networks with hidden nodes. We give a formulation of the scheduling problem an

When implementing a language by means of attribute grammars, it is often useful to study example programs and their attributed trees, to understand the compiler structure, or for debugging. DrAST is a tool that allows interactive inspection of attributed trees. It is interfaced to the JastAdd metacompiler, and supports all JastAdd attribution mechanisms, such as demand evaluation, reference attrib

Braided convolutional codes (BCCs) are a class of spatially coupled turbo-like codes (SC-TCs) with excellent belief propagation (BP) thresholds. In this paper we analyze the performance of BCCs in the finite block-length regime. We derive the average weight enumerator function (WEF) and compute the union bound on the performance for the uncoupled BCC ensemble. Our results suggest that the union bo

Collaborative filtering for recommender systems seeks to learn and predict user preferences for a collection of items by identifying similarities between users on the basis of their past interest or interaction with the items in question. In this work, we present a conjugate prior regularized extension of Hofmann's Gaussian emission probabilistic latent semantic analysis model, able to overcome th

We present a general purpose algorithm for finding low-weight codewords as well as for decoding a received codeword in any quasi-cyclic code whose length and dimension is a multiple of a power of 2. In this paper, we apply the algorithm on a McEliece variant recently proposed by Misoczki et al. (MDPC-McEliece: New McEliece variants from moderate density parity-check codes, 2013). In their paper, t

Massive MIMO is a promising technology for the coming 5G wireless systems. In this paper, a programmable baseband processor specifically designed for uplink symbol detection targeting massive MIMO is presented with a novel matrix inversion method proposed to obtain more precise and efficient computation. Including a microcode controlled channel preprocessing unit and a pipelined detection unit, th

The objective of this paper is to design a compressor for silicon debug that is suitable in an industrial Nexus environment. The compressor must operate in real-time and must be lossless. Important for the compressor is high compression ratio, low hardware cost and high throughput. We implemented the compression on an FPGA and we compared our implementation in terms of throughput and hardware cost

This paper presents a wideband quadrature radio receiver employing ΔΣ-based A/D-converting channel-select filters (ADCSFs). The output of the quadrature passive mixer is directly connected to the input of the ADCSFs, where a first-order ΔΣ modulator is incorporated into a fourth-order Butterworth channel-select filter (CSF) to provide sufficient dynamic range for a cellular system. A design method

One of the approaches to modify the McEliece cryptosystem to overcome its large key size is replacing binary Goppa codes with a new structured code. However, this modification makes such cryptosystems encounter some new attacks. There are a few modified McEliece cryptosystem variants which are known to be secure. One of them is the cryptosystem introduced by Baldi et al. which uses quasi-cyclic lo

The study concludes that there were contacts between Birka and western Finland throughout more or less the whole existence of the town. The earliest evidence of these contacts is from the 760s and the latest from the middle of the tenth century. Unlike other eastern material in Birka, which became much more frequent during the second half of the ninth century the contacts with Finland were constan

Due to the increasing number of infotainment and safety functions in vehicles, the need for reliable communication link is becoming very critical. A key consideration in providing a reliable link is the antenna performance, which is conventionally evaluated by its efficiency and ability to provide the required coverage upon integration in vehicles. However, modern vehicles are equipped with many e

A microstrip antenna integration with a power amplifier is presented for the 60 GHz band. The antenna is a single layer 4×4 square patches array. The power amplifier is injection locked, designed in a 65 nm CMOS technology, with single-ended input and output signals. The integration is realized by means of bond wire connections. The antenna and the power amplifier are fabricated, characterized and

The paper investigates the reduction of dynamic power for streaming applications yielded by asynchronous dataflow designs by using clock gating techniques. Streaming applications constitute a very broad class of computing algorithms in areas such as signal processing, digital media coding, cryptography, video analytics, network routing and packet processing and many others. The paper introduces a

The growing complexity of digital signal processing applications make a compelling case the use of high-level design and synthesis methodologies for the implementation on programmable logic devices and embedded processors. Past research has shown that, for complex systems, raising the level of abstraction of design stages does not necessarily come at a penalty in terms of performance or resource r

Dataflow programming is a paradigm for describing stream processing algorithms in a manner that naturally exposes their concurrency and makes the resulting programs readily implementable on highly parallel architectures. Dataflow programs are graph structured, with nodes representing computational kernels that process the data flowing over the edges. There are two major families of languages for t