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This paper presents a 28 GHz QVCO intended to be used in an 81-86 GHz E-band transceiver. E-band transceivers using e.g. 16 QAM modulation schemes are sensitive to I/Q phase error. Already a three degree error significantly degrades the bit error rate, and careful control of the phase error of the 28 GHz QVCO is therefore required. In the presented design the phase error can be tuned using four va

In many application domains, critical systems must comply with safety standards. This involves gathering safety evidence in the form of artefacts such as safety analyses, system specifications, and testing results. These artefacts can evolve during a system's lifecycle, creating a need for impact analysis to guarantee that system safety and compliance are not jeopardised. Although extensive resear

Recently, we proposed a design framework to obtain efficient and uncorrelated MIMO antennas in mobile handsets for frequencies below 1 GHz. The main benefit of the approach is that it can give significantly larger bandwidths than existing techniques. Using the Theory of Characteristic Modes, it has been shown that slightly modification of the chassis can result in multiple orthogonal resonant mode

Designing multiple antennas in small terminals at frequency bands below 1 GHz is challenging due to severe mutual coupling among antenna elements. The severe coupling is often the result of simultaneous excitation of the fundamental characteristic mode of the terminal chassis by more than one antenna element. In this work, through the use of characteristic mode analysis, we propose to solve the co

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

Evaluation of Specific Absorption Rate (SAR) for multiple antenna systems is expected with the upcoming deployment of LTE Advanced, where multi-antennas are excited in both uplink and downlink. In this work, the influence of different antenna locations and antenna types was investigated for stand-alone SAR and simultaneous SAR, to provide some guidelines for antenna design in multi-antenna handset

Open Innovation (OI) has attracted scholarly interest from a wide range of disciplines since introduced by Chesbrough, i.e. ”a paradigm that assumes that firms can and should use external ideas as well as internal ideas, and internal and external paths to market, as they look to advance their technology”. However, OI remains unexplored for software engineering (SE), although widespread in practice

Massive multiple-input multiple-output (MIMO) systems, where the base station (BS) is equipped with a large number of antennas and the mobile devices have a single antenna, can significantly enhance the system performance. In many wireless systems inter symbol interference (ISI) due to delay dispersion of the channel can dramatically affect the demodulation process of the received signals. Precodi

Healthcare is increasingly a collaborative effort in- volving caregivers from several different organizations providing services to the same patient. This is particularly the case in care for the elderly and chronically ill, where a preference for care in the home is common. Current systems lack support for care scenarios that require mobility and intra-organizational collaboration. This results i

Technology scaling in advanced CMOS nodes has been very successful in reducing the cost and increasing the operating frequency, however, it has also resulted in reduced transistor intrinsic gain and increased thermal noise coefficient, and most importantly, deteriorated linearity performance. At the same time, advanced wireless communication standards offer ever increasing data rates and pose m

This paper presents a 2-dimension (2-D) Vernier time-to-digital converter (TDC) which uses two 3-stage gated-ring-oscillators (GROs) in the X/Y Vernier branches. The already small Vernier quantization noise (~10.6ps) is improved by the 1st-order noise shaping of the GRO. Moreover, since all delay differences between X phases and Y phases can be used (rather than only the diagonal line of the 1-dim

Numerous tools automating various aspects of software engineering have been developed, and many of the tools are highly configurable through parameters. Understanding the parameters of advanced tools often requires deep understanding of complex algorithms. Unfortunately, suboptimal parameter settings limit the performance of tools and hinder industrial adaptation, but still few studies address the