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Clustering multiple motions from observed point trajectories is a fundamental task in understanding dynamic scenes. Most motion models require multiple tracks to estimate their parameters, hence identifying clusters when multiple motions are observed is a very challenging task. This is even aggravated for high-dimensional motion models. The starting point of our work is that this high-dimensionali
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 advent of 6G wireless communication marks a transformative era in technological connectivity, bringing forth challenges and opportunities alike. This paper unveils an innovative, open-source simulator, meticulously crafted for cell-free 6G wireless networks. This simulator is not just a tool but a gateway to the future, blending cutting-edge channel models with the simulation of both physical
Online platforms devoted to investigating criminal cases or mysteries are often seen as reaching outwards to identify suspects, promote punishment, and try to solve cases. Simultaneously, internal interactions between posters motivate them to contribute, even to outdo one another, and so a team spirit emerges. This article analyzes a lengthy thread on a Swedish Internet discussion forum, FlashbackOnline platforms devoted to investigating criminal cases or mysteries are often seen as reaching outwards to identify suspects, promote punishment, and try to solve cases. Simultaneously, internal interactions between posters motivate them to contribute, even to outdo one another, and so a team spirit emerges. This article analyzes a lengthy thread on a Swedish Internet discussion forum, Flashback
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
This paper presents an injection-locked frequency tripler for 28-GHz direct-conversion transceivers, which takes a differential input and outputs a quadrature signal. A feedback system is added to ensure that lock occurs and to keep the quadrature error below 1° across operating frequencies and process corners. Simulations show that the tripler can cover the entire 24-30 GHz band across all corner
mmWave communication has come up as the unexplored spectrum for 5G services. With new standards for 5G NR positioning, more off-the-shelf platforms and algorithms are needed to perform indoor positioning. An object can be accurately positioned in a room either by using an angle and a delay estimate or two angle estimates or three delay estimates. We propose an algorithm to jointly estimate the ang
Many concepts for future generations of wireless communication systems use coherent processing of signals from many distributed antennas. The aim is to improve communication reliability, capacity, and energy efficiency and provide possibilities for new applications through integrated communication and sensing. The large bandwidths available in the higher bands have inspired much work regarding sen
We verify safety of a nonlinear continuous-time system controlled by a neural network controller. The system is decomposed into low-dimensional subsystems connected in a feedback loop. Our application is a rocket landing, and open-loop properties of the two-dimensional altitude subsystem are verified using worst-case simulations. Closed-loop safety properties (crash-avoidance) of the full system a
In this paper, we present a multipath-based simultaneous localization and mapping (SLAM) algorithm that continuously adapts mulitiple map feature (MF) models describing specularly reflected multipath 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 mobil
Recent methods on privacy-preserving image-based localization use a random line parameterization to protect the privacy of query images and database maps. The lifting of points to lines effectively drops one of the two geometric constraints traditionally used with point-to-point correspondences in structure-based localization. This leads to a significant loss of accuracy for the privacy-preserving
This paper presents a high-speed comparator which employs a novel regeneration latch to enhance the comparison process. The regeneration stage employs an innovative mechanism that reduces the RC constant at the output while avoiding static power consumption. Furthermore, the proposed comparator is capable of operating seamlessly with a rail-to-rail input common-mode voltage. This is made possible
Understanding the evolution of multipath components (MPCs) in real radio channels is crucial to enhancing channel modeling and multipath-assisted positioning. This paper provides an experimental analysis of the behavior of MPCs originating from a standard building facade at millimeter wave (mmWave) frequencies. Utilizing a high-resolution channel parameter estimation method alongside a joint clust
A 12-bit time-interleaved (TI) analog-to-digital converter (ADC) with pipelined successive-approximation (SAR) channels is presented in this paper. The ADC consists of four TI channels, each incorporating a two-stage pipelined asynchronous SAR ADC. To facilitate clock distribution, a common bootstrapped sampler in front of the four channels is employed. The reset switch in the capacitive digital-t
