Real-time GNSS software receivers Challenges, status and perspectives

Chat with Graph Search

Ask any question about EPFL courses, lectures, exercises, research, news, etc. or try the example questions below.

DISCLAIMER: The Graph Chatbot is not programmed to provide explicit or categorical answers to your questions. Rather, it transforms your questions into API requests that are distributed across the various IT services officially administered by EPFL. Its purpose is solely to collect and recommend relevant references to content that you can explore to help you answer your questions.

With society’s increasing reliance on digital data sharing, the protection of sensitive information has become critical. Encryption serves as one of the privacy-preserving methods; however, its realization in the audio domain predominantly relies on signal processing or software methods embedded into hardware. In this paper, we introduce LenslessMic, a hybrid optical hardware-based encryption method that utilizes a lensless camera as a physical layer of security applicable to multiple types of audio. We sho

With the success of deep learning in the past decade, neural networks transitioned from simple layer stacking to sophisticated, highly complex designs. This article provides an overview of such deep learning architectures for sequence modeling, with a focus on their core mathematical principles: 1) we review the evolution of common sequence models from recurrent neural networks (RNNs), to Transformers, and modern state-space models (SSMs), exploring their foundational components such as gating, attention, a

This work presents a compact (31.5×10.7×4mm3) video encoder system with a commercial imager, flash, a custom 2×2 microlens array, and an image signal processing (ISP) chip using novel 2×2 intra-frame compression. Leveraging the subframe redundancies inherent to the microlens array, the system achieves >59× compression with >32dB PSNR. With this, the ISP chip fabricated in 28nm CMOS attains 90.6 pJ/pixel energy efficiency at 1280×800, 65fps video stream.

Biological impedance (BioZ) is an information-packed modality that allows for non-invasive monitoring of health and emotional state. Currently, most research involving tissue impedance is based on bulky or fixed-purpose hardware, which limits the scope of research and the possibilities of experiments. In this work, we present HEEPidermis: a System-on-Chip (SoC) which integrates all the blocks needed for tissue impedance measurement, including two 8-bit, arbitrary-signal current DACs, two VCO-based ADCs, and

Fully implantable systems such as neural interfaces require wireless power delivery to eliminate bulky batteries and reduce the need for replacement surgeries. The growing functional complexity of implants, which now integrate sensing, stimulation, signal processing, and machine learning [1], continues to increase their power demands. These devices have diverse power needs, with high-power modes during training and low-power operation during inference, making flexible and efficient power delivery essential

Performance-oriented applications require efficient locks to harness the computing power of multicore architectures. While fast, spinlock algorithms suffer severe performance degradation when thread counts exceed available hardware capacity, i.e., in oversubscribed scenarios. Existing solutions rely on imprecise heuristics for blocking, leading to suboptimal performance. We present FlexGuard, the first approach that systematically switches from busy-waiting to blocking precisely when a lock-holding thread i

CAPE is a European-funded project targeting to reshape edge-cloud computing by defining edge micro data centers as a new unit of computing. Fully committing to open source, CAPE develops a fully Composable Infrastructure (CI) for high-performance edge server hardware platforms grounded in open, forward-looking standards. Together with an open-source software stack covering the Edge-Cloud Continuum, this holistic approach boosts power and energy efficiency while reducing resource overprovisioning. Completely

The SKA Regional Centres Network (SRCNet) of globally distributed data centers will have to find innovative ways to store and disseminate some 600Pbytes/year of incoming data products from SKAO while providing the necessary federated computing resources to the research community to analyze it. As the amount SKAO data continues to grow over its 50+ years lifespan, the salability of SRCNet's capabilities to cater data and computing services to the scientific community will be critical to the meet SKAO’s Scien

The conventional idea of analog computing has recently been revived by recent developments of the fields of metamaterials and ultrafast optics, allowing one to perform signal-processing tasks at the speed of wave propagation with high efficiency. Despite these advantageous features, the functionality of such wave-based computing systems, like any other analog system, is mitigated by the sensitivity and geometrical tolerances of analog components, causing uncertainties in the computation process. Here, we pr

In the last years, Global Navigation Satellite System (GNSS) based navigation in high earth orbits (HEOs) has become a research field of interest, since it can increase the spacecraft’s autonomy, reducing the operating costs. However, the GNSS availability and the GNSS-based navigation performance for a spacecraft orbiting above the GNSS constellation, is strongly constrained by the signals’ power levels at the receiver position and by its sensitivity. The simulated level of signal power at the receiver’s p

“A critical dominant trend in the evolution of the electronics industry is the incredible growth in the sheer number of devices that are being deployed annually across a wide range of applications. Many of these devices are being leveraged to provide interfaces between the analog world and the digital infrastructure that supports the Internet of Everything, providing environmental sensing data to drive more effective pollution management, component data to enhance equipment lifetime and automate repair sche

The problem of recovering a structured signal

\mathbf{x} \in \mathbb{C}^p

from a set of dimensionality-reduced linear measurements

\mathbf{b} = \mathbf {A}\mathbf {x}

arises in a variety of applications, such as medical imaging, spectroscopy, Fourier optics, and computerized tomography. Due to computational and storage complexity or physical constraints imposed by the problem, the measurement matrix

\mathbf{A} \in \mathbb{C}^{n \times p}

is often of the form $\mathbf{A} = \mathbf{P}_{\Omega}\boldsymbo

Wireless Body Sensor Nodes (WBSNs) are miniaturized and ultra-low-power devices, able to acquire and wirelessly trans- mit biosignals such as electrocardiograms (ECG) for extended periods of times and with little discomfort for subjects [1]. Energy efficiency is of paramount importance for WBSNs, because it allows a higher wearability (by requiring a smaller battery) and/or an increased mean time between charges. In this paper, we investigate how noise-aware design choices can be made to minimize energy con

We introduce a recursive algorithm for performing compressed sensing on streaming data. The approach consists of a) recursive encoding, where we sample the input stream via overlapping windowing and make use of the previous measurement in obtaining the next one, and b) recursive decoding, where the signal estimate from the previous window is utilized in order to achieve faster convergence in an iterative optimization scheme applied to decode the new one. To remove estimation bias, a two-step estimation proc

This chapter presents the various positioning technologies used in pedestrian navigation. The basic principles as well as the main advantages and disadvantages of positioning methods in the context of urban mobility are discussed. The development of navigation systems has led to the establishment of digital navigation maps containing the network of different traffic routes. In the future, pedestrian navigation technology, both attractive and feared, will be accepted if legal and commercial regulations of us

In many applications, the sampling frequency is limited by the physical characteristics of the components: the pixel pitch, the rate of the A/D converter, etc. A low-pass filter is then often applied before the sampling operation to avoid aliasing. However, when multiple copies are available, it is possible to use the information that is inherently present in the aliasing to reconstruct a higher resolution signal. If the different copies have unknown relative offsets, this is a non-linear problem in the off

A navigation process is to start from a known (initial) position and to ensure a continued localisation of the user during the movement. Consider a pedestrian navigation system which contains a GPS receiver and a set of inertial sensors connected with the map database. The problem to solve is to determine the users location using the map database and measurements of the inertial sensors. Indoors the position of each step is determined as a function of the previous position and inertial measurements. Thus th

Optical Coherence Tomography (OCT) is a recent biomedical imaging technique based on low-coherence interferometry that is capable of acquiring depth-resolved reflectivity maps of scattering tissues with high sensitivity. The conventionally employed imaging mode is to build up a cross sectional image by scanning the sample surface with a point illumination. In order to increase imaging speed, the concept of parallel detection has been introduced to OCT. Here, a whole sample line or even surface is imaged dir

Measurement of the plasma generated diamagnetic flux on tokamak a configuration variable (TCV) is used to derive the plasma pressure, as on other magnetic confinement experiments. However, specificities of the device make the measurement more difficult: for passive stabilization of the vertical position of highly elongated plasmas, the vessel has a low electrical resistivity, leading to large image currents in the vessel. For the same reason the plasma must also be kept close to the conducting wall, so that

Summary The continuous wavelet transform (CWT) is a common signal-processing tool for the analysis of nonstationary signals. We propose here a new B-spline-based method that allows the CWT computation at any scale. A nice property of the algorithm is that the computational cost is independent of the scale value. Its complexity is of the same order as that of the fastest published methods, without being restricted to dyadic or integer scales. The method reduces to the filtering of an auxiliary (pre-integrate

Real-time GNSS software receivers Challenges, status and perspectives

Chat with Graph Search

LenslessMic: Audio Encryption and Authentication via Lensless Computational Imaging

Sequence Modeling Architectures: Foundations [Special Issue on the Mathematics of Deep Learning]

A 90.6 pJ/pixel 1280×800 65 fps cm-Scale Fully Integrated Video Encoder System Utilizing a 2×2 Microlens Array

HEEPidermis: a versatile SoC for BioZ recording

A Magnetoelectric Wireless Power Transfer System with a 97.25%-Efficient Load-Adaptive CMOS Rectifier for Miniaturized Implants

FlexGuard: Fast Mutual Exclusion Independent of Subscription

CAPE - European Open Compute Architecture for Powerful Edge

Scaling Sustainable Computing New Methods for Enhancing Efficiency in the SKA Regional Data Centers

Solving differential equations with topological acoustic metamaterials

GPS based navigation performance analysis within and beyond the Space Service Volume for different transmitters’ antenna patterns

Short Course: Modeling for Ultra-Low-Power Analog Design

Learning-Based Compressive Subsampling

Hardware-Software Inexactness in Noise-aware Design of Low-Power Body Sensor Nodes

Recursive Compressed Sensing

Pedestrian Navigation for the Benefit of Mobility

Aliasing is Good for You: Joint Registration and Reconstruction for Super-Resolution

Map-matching for pedestrians via Bayesian inference

Innovative experimental concepts for optical coherence tomography

Fast single loop diamagnetic measurements on the TCV tokamak

Continuous Wavelet Transform with Arbitrary Scales and O(N) Complexity