The AXIOM software layers

AXIOM project aims at developing a heterogeneous computing board (SMP-FPGA).The Software Layers developed at the AXIOM project are explained.OmpSs provides an easy way to execute heterogeneous codes in multiple cores. People and objects will soon share the same digital network for information exchange in a world named as the age of the cyber-physical systems. The general expectation is that people and systems will interact in real-time. This poses pressure onto systems design to support increasing demands on computational power, while keeping a low power envelop. Additionally, modular scaling and easy programmability are also important to ensure these systems to become widespread. The whole set of expectations impose scientific and technological challenges that need to be properly addressed.The AXIOM project (Agile, eXtensible, fast I/O Module) will research new hardware/software architectures for cyber-physical systems to meet such expectations. The technical approach aims at solving fundamental problems to enable easy programmability of heterogeneous multi-core multi-board systems. AXIOM proposes the use of the task-based OmpSs programming model, leveraging low-level communication interfaces provided by the hardware. Modular scalability will be possible thanks to a fast interconnect embedded into each module. To this aim, an innovative ARM and FPGA-based board will be designed, with enhanced capabilities for interfacing with the physical world. Its effectiveness will be demonstrated with key scenarios such as Smart Video-Surveillance and Smart Living/Home (domotics).Peer ReviewedPostprint (author's final draft

D21.3 Analysis of initial results at EuWIN@CTTC

Deliverable D21.3 del projecte europeu NEWCOM#The nature of this Deliverable of WP2.1 (“Radio interfaces for next-generation wireless systems”) is mainly descriptive and its purpose is to provide a report on the status of the different Joint Research Activities (JRAs) currently ongoing, some of them being performed on the facilities that are available at EuWInPeer ReviewedPreprin

Bayesian nonlinear filtering using quadrature and cubature rules applied to sensor data fusion for positioning

International audienceThis paper shows the applicability of recently-developed Gaussian nonlinear filters to sensor data fusion for positioning purposes. After providing a brief review of Bayesian nonlinear filtering, we specially address square-root, derivative-free algorithms based on the Gaussian assumption and approximation rules for numerical integration, namely the Gauss-Hermite quadrature rule and the cubature rule. Then, we propose a motion model based on the observations taken by an Inertial Measurement Unit, that takes into account its possibly biased behavior, and we show how heterogeneous sensors (using time-delay or received-signal-strength based ranging) can be combined in a recursive, online Bayesian estimation scheme. These algorithms show a dramatic performance improvement and better numerical stability when compared to typical nonlinear estimators such as the Extended Kalman Filter or the Unscented Kalman Filter, and require several orders of magnitude less computational load when compared to Sequential Monte Carlo methods, achieving a comparable degree of accuracy

Nonlinear filtering for ultra-tight gnss/ins integration

International audienceThis paper considers the problem of ultra--tight GNSS/INS integration. We propose a new approach, deriving the direct relation between Inertial Measurement Unit (IMU) measurements and synchronization parameters, used in the trilateration algorithm to compute the position of the receiver. We take into account the IMU's eventual biased behavior by introducing it into the state representation. We use a recently--developed, square-root derivative--free Gaussian nonlinear filter to solve the estimation problem

Implementation of GNSS receiver hardware accelerators in all-programmable system-on-chip platforms

This paper reports the design and proof-of-concept implementation of hardware accelerator modules for a low power consumption and small form factor software-defined GNSS receiver using an all-programmable System-On-Chip (SoC) platform. An all-programmable SoC is a device that integrates the software reprogrammability of a CPU with the hardware reprogrammability of an FPGA. The presented approach takes advantage of the flexibility of software-defined radio technology, and the power efficiency and small form factor of a SoC, to implement a portable fully customizable GNSS receiver with the capability to process GNSS signals in real-time and to deliver GNSS products in standard formats. The SoC runs a free and open source software implementation of a multi-band, multi-system GNSS receiver released under the General Public License v3.0 and available in a public source code repository. However, the most computationally demanding tasks are offloaded to the FPGA and implemented as hardware acceleration modules. The hardware acceleration modules can take advantage of the inherent parallelism in the GNSS receiver signal processing functions. A review of the GNSS receiver architecture is presented, together with an overview of the software and a design description of the hardware accelerators in the SoC. A dual-band proof of concept GNSS receiver is exposed, together with some results.This work was supported by the Spanish Ministry of Economy and Competitiveness through project TEC2015-69868-C2-2-R (ADVENTURE).Peer ReviewedPostprint (author's final draft

Sequential Monte-Carlo Approximation to the ML Time-Delay Estimator in a Multipath Channel

In direct--sequence spread--spectrum (DS--SS) based navigation systems, multipath can seriously degrade synchronization performance causing time delay and code phase estimates to deviate from the actual value. These biases depend on the relative amplitudes and delays of multipath replicas with respect to the direct signal. The error in the estimated position due to multipath, when using a standard Delay Lock Loop, can be on the order of several tens of meters, which constitutes a critical aspect in high--precision applications. This paper presents a Sequential Monte Carlo based algorithm which tries to iteratively attain the ML estimate of synchronization parameters of the direct signal and multipath replicas

Advances in the Theory and Implementation of GNSS Antenna Array Receivers. In "Microwave and Millimeter Wave Circuits and Systems: Emerging Design, Technologies and Applications", Edited by A. Georgiadis, H. Rogier, L. Roselli, P. Arcioni

The chapter focuses on recent developments in the field of antenna arrays applied to the design of robust, high-performance global navigation satellite system (GNSS) receivers