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Fifth generation cellular systems will be deployed in the microwave and millimeter–wave (mmWave) frequency bands (i.e., between 0.5–100 GHz). Propagation characteristics at these bands have a fundamental impact on each aspect of the cellular architecture, ranging from equipment design to real-time performance in the field. While we have a reasonable understanding of the propagation characteristics

Programming languages are ever evolving, with new languages being invented to solve new problems, and old languages being extended to solve old problems in new ways. With the continued evolution of programming languages, and with new and improved static program analyses, we need flexible systems for building our static analyses and compilers. Declarative programming with Reference Attribute Gramma

Knowing whether a software feature will be completed in its planned iteration can help with release planning decisions. However, existing research has focused on predictions of only low-level software tasks, like bug fixes. In this paper, we describe a mixed-method empirical study on three large IBM projects. We investigated the types of iteration changes that occur. We show that up to 54% of high

Datalog has emerged as a powerful tool for expressing staticprogram analyses. Program analysis researchers have builtnontrivial code bases in Datalog, but tool support for workingwith Datalog itself has been lacking. In this paper, weintroduce MetaDL, a language extension to Datalog thatenables source-level Datalog program analysis within Datalog.We describe several program analyses implemented in

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

Further exploitation of the spatial domain, as in Massive MIMO (MaMi) systems, is imperative to meet future communication requirements [1]. Up-scaling of conventional 4×4 small-scale MIMO implementations to MaMi is prohibitive in-terms of flexibility, as well as area and power cost. This work discloses a 1.1mm2 128×8 MaMi baseband chip, achieving up to 12dB array and 2× spatial multiplexing gains.

Measuring MIMO-SAR is an important part of mobile handset evaluation, following the introduction of uplink MIMO transmission schemes in LTE-Advanced. However, the measurement of MIMO-SAR is complex and time-consuming. In this paper, 6 unique dual-antenna mobile handsets, including both typical and novel designs, are analyzed to determine the dependence of MIMO-SAR on antenna configuration and corr

This paper presents a study on iconic programming support for mainly position-based lead-through programming of an ABB YuMi collaborative robot. A prototype tool supporting a hybrid programming and execution mode was developed and evaluated with 21 non-expert users with varying programming and robotics experience. We also present a comparison of the programming times for an expert robot programmer

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

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

Deciding the optimal project scope that fulfills the needs of the most important stakeholders is challenging due to a plethora of aspects that may impact decisions. Large companies that operate in rapidly changing environments experience frequently changing customer needs which force decision makers to continuously adjust the scope of their projects. Change intensity is further fueled by fierce ma

A wide band fractional-N digital PLL which uses a high resolution 2-dimension gated-Vernier time-to-digital converter (TDC) with 5.2 ps resolution is presented. The quantization noise shaping of the TDC greatly improves the in-band phase noise. While, in the same time, the 2-dimension structure makes the digital PLL (DPLL) be able to process large phase errors almost without the influence of laten

In this work we implement features for IEEE 802.11ac in the NS-3 simulator, in particular wider channels and bit-error calculations for higher modulation coding schemes. We also implement four wireless LAN deployment scenarios from the 802.11ax working group scenario document, and evaluate their performance under different operating conditions. Our simulation results demonstrate that many nodes in

Block diagram languages are often used for physical modeling and automation, where end users are domain engineers that instantiate block types and wire them together. Abstraction mechanisms in these languages allow specialists to build advanced reusable domain-specific libraries. However, this brings a tension between supporting reusability and making the language simple to comprehend for domain e

Ensuring that communication is secure, including the ability to encrypt sensitive traffic, has always been a fundamental pillar of the telecom industry. Users expect their right to privacy to be respected, and operators expect to be able to protect themselves and their customers from various kinds of attacks. But the world is changing. Encryption technologies are advancing, regulations are changin

We consider optimal precoder design for multi-user multiple-input multiple-output (MIMO) broadcasting channels in single-carrier (SC) systems. Instead of linear detection, we assume that advanced non-linear channel shortening (CS) detectors are utilized at the receivers. Such a scenario is challenging for precoder design as the uplink-downlink duality is inapplicable. The target of our linear prec

This dissertation presents the design and implementation of a new block diagram programming language, Bloqqi, for building control systems with focus on variability. The language has been developed in collaboration with industry with the goal of reducing engineering time and improving reuse of functionality.When building a control system for a plant, there are typically different variants of the s

In multipath routing, maximization of the cardinality K of the disjoint-path set for a given source and destination assuming an upper bound on the differential delay D is one of the key factors enabling its practical applications. In the paper we study such an optimization problem for multipath routing involving maximization of K under the D constraint as the primary objective, and then minimizati