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Quality requirements play a critical role in driving architectural design and are an important issue in software development. Therefore, quality requirements need to be considered, specified, and quantified early during system analysis and not later in the development phase in an ad-hoc fashion. This paper presents the quality performance model that estimates quality targets in relation to market
Software development companies operating in market-driven domains need to deliver new and appealing software products at an increasing rate in order to stay competitive. This requires fast and efficient development of software for which the requirements are based on ever-changing market demands. Agile development claims to achieve increased development efficiency by performing the requirements eng
Three areas of ongoing research in channel coding are surveyed, and recent developments are presented in each area: spatially coupled Low-Density Parity-Check (LDPC) codes, non-binary LDPC codes, and polar coding.
Correlation coefficient, as a critical performance metric of multiple antenna systems, can be calculated from the 3D radiation patterns of the antennas for multipath environments with uniform 3D angular power spectrum. A simpler, faster and lower cost approach uses the antennas’ scattering parameters to determine correlation coefficient. However, the method assumes lossless antennas, and hence onl
Open Source Software (OSS) created a paradigm shift within the software engineering field prompting further research to understand how mature, industry grade, software can be produced in an online milieu with distributed and lightly managed developers contributing source code in their free time. The OSS has become also a major revenue generator for many commercial organizations, and has found its
Correlation coefficient of received signals across a pair of antennas is a key performance indicator for multiple-input multiple-output (MIMO) systems. For multipath environments with uniform 3D angular power spectrum, the signal correlation between two antennas can be exactly calculated from their 3D radiation patterns. When radiation patterns are unavailable, a simplified approach that only requ
A 12 GHz PLL with digital output phase control has been implemented in a 90 nm CMOS process. It is intended for LO signal generation in integrated phased array transceivers. Locally placed PLLs eliminate the need of long high frequency LO routing to each transceiver in a phased array circuit. Routing losses are thereby reduced and the design of integrated phased array transceivers becomes more mod
The use of duty-cycled ultralow-power wake-up receivers (WRxs) can significantly extend a node lifetime in low-power sensor network applications. In the WRx design, both the low-power operation of the WRx and the wake-up beacon (WB) detection performance are of importance. We present a system-level analysis of a duty-cycled WRx design, including an analog front end, a digital baseband, the WB stru
Abstract in UndeterminedIn this paper, we present and evaluate the performance of a dynamic dual-link wideband multiple-input-multiple-output ( MIMO) channel sounder. The channel sounder can simultaneously measure two wideband dual-polarized links, each with a MIMO matrix size of 30 x 30 and 30 x 32. Multi-link MIMO systems, including multiuser and cooperative MIMO, are essential parts of future h
We deal with the construction of optimal channel shortening, also known as combined linear Viterbi detection, algorithms for ISI and MIMO channels. In the case of MIMO channel shortening, the tree structure to represent MIMO signals is replaced by a trellis. The optimization is performed from an information theoretical perspective and the achievable information rates of the shortened models are de
We perform a minimum distance analysis of a class of two-dimensional intersymbol interference (ISI) channels applicable to multitrack magnetic recording and orthogonal frequency division multiplex transmission systems. Exact minimum distance for a wide class of ISI responses is derived. The fundamental analytical technique is to transform the channel into an equivalent minimum phase channel. The r
The popularity of Open Source Software (OSS) has increased the interest in using it in safety critical applications. The aim of this study is to review research carried out on usage of open source code in development of safety-critical software and systems. We conducted a systematic mapping study through searches in library databases and manual identification of articles from open source conferenc
Ecosystem governance becomes gradually more relevant for a set of companies or actors characterized by symbiotic relations evolved on the top of a technological platform, i.e. a software ecosystem. In this study, we focus on the governance of a hardware-dependent software ecosystem. More specifically, we evaluate the governance model applied by Axis, a network video and surveillance camera produce
We consider the problem of constructing linear precoders for quasi-stationary multiple-input multiple-output channels. Maximum-likelihood detection is assumed and the objective of the precoding is to maximize the minimum Euclidean distance of the signaling. Since the channel remains constant for some time, the precoding is performed spatially as well as across time. As will be shown, the precoder
This paper presents two circuits, a complete 1.5 V 28 GHz SiGe beam steering PLL and a standalone 28 GHz QVCO with I/Q phase imbalance detection and compensation. The circuits were designed in a SiGe process with f T = 200 GHz. The PLL is intended to be used for beam steering in an 81–86 GHz E-band transmitter. Phase control is implemented by DC current injection at the output of a Gilbert archite
