Dates and Events: |
OSADL Articles:
2023-11-12 12:00
Open Source License Obligations Checklists even better now
Import the checklists to other tools, create context diffs and merged lists
2022-07-11 12:00
Call for participation in phase #4 of Open Source OPC UA open62541 support project
Letter of Intent fulfills wish list from recent survey
2022-01-13 12:00
Phase #3 of OSADL project on OPC UA PubSub over TSN successfully completed
Another important milestone on the way to interoperable Open Source real-time Ethernet has been reached
2021-02-09 12:00
Open Source OPC UA PubSub over TSN project phase #3 launched
Letter of Intent with call for participation is now available |
COOL - Compact OSADL Online Lectures - November 2024 edition
OSADL talks at ESE Embedded Software Engineering Kongress
COOL - Compact OSADL Online Lectures - December 2024 edition
Real Time Linux Workshops
1999 - 2000 - 2001 - 2002 - 2003 - 2004 - 2005 - 2006 - 2007 - 2008 - 2009 - 2010 - 2011 - 2012 - 2013 - 2014 - 2015
13th Real-Time Linux Workshop from October 20 to 22 at the Faculty of Electrical Engineering, Czech Technical University in Prague
Announcement - Hotels - Directions - Agenda - Paper Abstracts - Presentations - Registration - Abstract Submission - Sponsoring - Gallery
The Witch Navigator - A Software GNSS Receiver Built on Real-Time Linux
Petr Kacmarik, Czech technical university in Prague, Faculty of electrical engineering, Department of Radio engineering
Pavel Kovar, Czech technical university in Prague, Faculty of electrical engineering, Department of Radio engineering
Ondrej Jakubov, Czech technical university in Prague, Faculty of electrical engineering, Department of Radio engineering
Frantisek Vejrazka, Czech technical university in Prague, Faculty of electrical engineering, Department of Radio engineering
The Witch Navigator (WNav) is an open source project of GNSS (Global Navigation Satellite System) receiver whose hardware is implemented as an ExpressCard hosted in PC with Linux OS.
The employment of PC offers a possibility of an easy implementation of signal processing algorithms since almost no restrictions are introduced by a specific embedded platform (concerning memory requirements or real data type and its arithmetic). As a consequence, the WNav is especially suitable for researchers or students because the signal processing algorithms can there be implemented in a similar manner as in high-level simulations. Furthermore, developers can rely on the wide and well known collection of development tools for Linux on x86 architecture. Unlike similar projects, WNav has capability to achieve performance comparable to professional GNSS receivers.
The WNav receiver is equipped with two front ends which can process any civil GNSS signals on two frequencies simultaneously. The whole receiver task is distributed between the device driver, user space real-time process and other auxiliary processes. The real-time needs are satisfied with RT_PREEMPT kernel patch.
The paper describes the whole conception of WNav with focus on the kernel part (device driver) and the real-time user space process, provides information about the processes synchronization and presents the achieved performance. The first obvious milestone is to develop the fully functional GPS L1 C/A receiver which justifies the selected conception. The achieved results and experience with this legacy signal are presented in the paper, as well.
