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In this paper, we study the influence of current localization on the isolation between two antennas in a compact terminal setting. The two antennas are chosen to be a monopole and a PIFA, respectively. The degree of current localization is controlled by the permittivity value of the PIFA’s dielectric loading. Both lossless and lossy cases are simulated in order to ascertain the underlying performa

It is known that the compactness of mobile terminals complicates the design of multiple antennas, since coupling between the antennas increases when they are placed in proximity of one another. While it is possible to mitigate coupling between closely spaced antennas, a tradeoff in bandwidth is required. In this paper, we highlight ground plane excitation as an additional dimension to consider in

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

We study the differentiability of the CIR process with respect to its parameters. We give a stochastic representation for these derivatives in terms of the paths of V.

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