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Accurate characterization of large-scale antenna arrays is growing in importance and complexity for the fifth-generation (5G) and beyond systems, as they feature more antenna elements and require increased overall performance. The full 3D patterns of all antenna elements in the array need to be characterized because they are in general different due to construction inaccuracy, coupling, antenna ar
In dual control, the manipulated variables are used to both regulate the system and identify unknown parameters. The joint probability distribution of the system state and the parameters is known as the hyperstate. The paper proposes a method to perform dual control using a deep reinforcement learning algorithm in combination with a neural network model trained to represent hyperstate transitions.
Cellular-connected unmanned aerial vehicle (UAV) has attracted a surge of research interest in both academia and industry. To support aerial user equipment (UEs) in the existing cellular networks, one promising approach is to assign a portion of the system bandwidth exclusively to the UAV-UEs. This is especially favorable for use cases where a large number of UAV-UEs are exploited, e.g., for packa
Square Kilometer Array (SKA) is a project aimed to build the largest radio telescope in the world and it has just gotten into the construction phase. In this phase, the ability to develop and integrate software in an integration environment is crucial as it is the ability to visualize system-related information via a User Interface to rapidly verify the correctness of the system behavior and spot
We study the stability of oscillation in two different multi-mode harmonic oscillators by means of Barkhausen’s criterion, involving a minimum of mathematical machinery in favor of a more intuitive, circuit-based approach. The results of the theoretical analysis match very closely those obtained through transient simulations, confirming occasionally surprising outcomes of the latter.
Avoidance maneuvers at normal driving speed or higher are demanding driving situations that force the vehicle to the limit of tire–road friction in critical situations. To study and develop control for these situations, dynamic optimization has been in growing use in research. One idea to handle such optimization computations effectively is to divide the total maneuver into a sequence of sub-maneu
To study the effects of uncertainty in autonomous motion planning and control, an 8-DOF model of a tractor-semitrailer is implemented and analyzed. The implications of uncertainties in the model are then quantified and presented using sensitivity analysis and closed-loop simulations. The study shows that different model parameters are more or less critical depending on the investigated scenario. U
In this study, we simulate the automatic control of an electric wheelchair for indoor Pac-Man-style navigation using solely thought commands. We delve into the decision-making mechanisms of an operational EEG-based brain computer interface that employs a visual oddball paradigm. We investigate strategies to enhance the efficiency of decision-making processes, aiming to accelerate response times wh
Modern robotic perception is highly dependent on neural networks.It is well known that neural network-based perception can be unreliable in real-world deployment,especially in difficult imaging conditions.Out-of-distribution detection is commonly proposed as a solution for ensuring reliability in real-world deployment.Previous work has shown that normalizing flow models can be used for out-of-dist
This paper presents a comparison between a Itl-bit asynchronous SAR (ASAR) ADC and a 10-bit synchronous SAR (SSAR) ADC, both designed and simulated in a 22-nm FDSOI CMOS process. To further support the simulation results, the ASAR ADC has also been fabricated and measurements are pre-sented. As opposed to the abrupt SNDR collapse in the SSAR ADC, the SNDR of the ASAR ADC shows a more graceful deg-
Hybrid analog-digital beamforming stands out as a key enabler for future communication systems with a massive number of antennas. In this paper, we investigate the hybrid precoder design problem for angle-of-departure (AoD) estimation, where we take into account the practical constraint on the limited resolution of phase shifters. Our goal is to design a radio-frequency (RF) precoder and a base-ba
The anticipated introduction of multi-GHz channel bandwidths in 6G makes integrated passive baseband filters very attractive. This work presents techniques to obtain high stop-band attenuation in a compact 4.7-GHz 5th-order passive baseband filter. A lumped model of the filter inductors is derived, and a capacitive cancellation technique is proposed, along with techniques to reduce inductive coupl
Software analytics (SA) is frequently proposed as a tool to support practitioners in software engineering (SE) tasks. We have observed that several secondary studies on SA have been published. Some of these studies have overlapping aims and some have even been published in the same calendar year. This presents an opportunity to analyze the congruence or divergence of the conclusions in these studi
In this paper, we present a multipath-based simultaneous localization and mapping (SLAM) algorithm that con-tinuously adapts mulitiple map feature (MF) models describing specularly reflected multi path components (MPCs) from flat surfaces and point-scattered MPCs, respectively. We develop a Bayesian model for sequential detection and estimation of interacting MF model parameters, MF states and mob
This paper presents millimeter-wave scattering from a building facade predominantly composed of windows. These windows are integrated into the walls, forming dihedral structures that reflect waves toward the incident angle. The scattered field resulting from the building facade is simulated using the two-bounce Geometrical-Physics (GO) method. We analyze the channel in power loss and arrival angle
An accurate description of the wireless channel is essential to the development of modern wireless systems. In order to mathematically model the propagation channel, one important prior step often done is high-resolution parameter estimation. The estimation accuracy of this step has a significant impact on how well the channel models can represent reality. In this paper, we address this by improvi
Distributed massive multiple-input multiple-output (MIMO) communication is envisioned as one of the key paradigms of future MIMO systems. To investigate non-wide-sense stationarities (non-WSSs) in distributed massive MIMO channels, this paper first presents an indoor channel measurement campaign, where distributed arrays with a total of 128 elements were implemented. Then relying on the correlatio
Electromagnetic degrees of freedom are instrumental in antenna design, wireless communications, imaging, and scattering. A large number of degrees of freedom enhance control in antenna design, influencing radiation patterns and directivity, while in communication systems, it links to spatial channels for increased data rates, reliability, and resolution in imaging. The correlation between computed
The geometry-based stochastic channel models (GSCM), which can describe realistic channel impulse responses, often rely on the existence of both local and far scatterers. However, their visibility from both the base station (BS) and mobile station (MS) depends on their relative heights and positions. For example, the condition of visibility of a scatterer from the perspective of a BS is different
This paper presents a 4-channel time-interleaved (TI) analog-to-digital converter (ADC), where each channel is comprised of a two-stage pipelined asynchronous successive-approximation (ASAR) sub-ADC. The ADC employs two samplers to alleviate the problem of timing skew on the sub-sampler when distributing the clock to the TI channels. To further increase the speed of the ADC, the reset switch in th
