Precise Positioning for Railway Vehicles

Precise Positioning for Railway Vehicles
Address: Tallysman Wireless Incorporated
36 Steacie Drive
Ottawa
Ontario
Canada K2K 2A9
Phone: +1 613 591 3131 Connect: Website: View website Contact: Contact supplier View: View supplier Download: Download

Tallysman Wireless Inc.

Precise Positioning for Railway Vehicles

Achieving Reliable Train Location with GNSS Solutions

This article first appeared in the Railway-News magazine, Issue 3 2022.

Government agencies in North America (e.g. US Federal Railroad Administration), Europe (e.g. European Union Agency for Railways) and other jurisdictions are looking to increase productivity and improve rail safety by applying new GNSS precise-positioning technology.

Mass-market GNSS receivers are built into cell phones, cameras and first-generation automotive navigation systems. These GNSS receivers use satellite PRN code signal timing to determine the difference between transmit and receive time and then derive the satellite’s range to the GNSS antenna. Latitude, longitude, height (of the antenna) and time can all be estimated with range measurements from four satellites. With a clear sky view, this technique, known as code tracking, can provide horizontal positioning within a 2–3m diameter to a 95% confidence level.

But rail applications commonly require sub-10cm precision, only achievable with multi-constellation, multi-frequency receivers in realtime kinematic (RTK) systems or commercial, wide-area corrections services. Real-time RTK systems rely upon GNSS signal carrier phase measurements to achieve the accuracy needed for positive train control (PTC).

An RTK system consists of a base reference receiver at a known location, a rover (the train), and a communication system to transmit base station coordinates and GNSS observables to the rover. The RTK technique provides excellent performance (rapid convergence and accuracy) when the baseline (base to rover) is short (≤30km). In this case, the base and rover receivers largely have common signal paths so that differencing techniques can be used to cancel many common errors, thereby providing for estimation of a distance vector between the known base station location and the unknown rover location.

An analogy would be to imagine the distance vector between base and rover as a measuring tape with imprecision of 1mm at the base station (VeraPhase / VeraChoke) and either 2mm (VeroStar) or 8mm (TW3972) at the rover (train).

Download full PDF here.

tallysman.com

Latest Tallysman Wireless Inc. News

TALLYMATICS Introduces the TW5390 Smart Antenna

TALLYMATICS Introduces the TW5390 Smart Antenna

TALLYMATICS Inc., a division of Tallysman Wireless, is excited to introduce its latest Smart Antenna to the market, the TW5390 Smart Antenna.

Tallysman Adds Housed TW3885T Dual-Band (L1/L5) Timing Antenna

Tallysman Adds Housed TW3885T Dual-Band (L1/L5) Timing Antenna

Tallysman® Wireless adds the housed TW3885T dual-band (L1/L5) timing antenna to its industry-leading line of GNSS products.

Tallysman Adds Extended Filtering (XF) To Their Helical Antennas

Tallysman Adds Extended Filtering (XF) To Their Helical Antennas

Tallysman® Wireless is excited to announce that it has added eXtended Filtering (XF) to their helical antennas.

Tallysman Adds to Its Industry-Leading Line of Helical Antennas

Tallysman Adds to Its Industry-Leading Line of Helical Antennas

Tallysman's new HC885EXF and HC885XF helical antennas are ideal for a variety of applications, including UAV's for land, sea and air.

Tallysman Adds eXtended Filtering (XF) to Verostar® GNSS Antennas

Tallysman Adds eXtended Filtering (XF) to Verostar® GNSS Antenna...

Tallysman® Wireless announced that it has added eXtended Filtering (XF) to the full line of VeroStar® precision GNSS antennas.

Tallysman® Adds to the TW7000 Line of Surface-Mount Antennas

Tallysman® Adds to the TW7000 Line of Surface-Mount Antennas

Tallysman® has added Galileo-E6, QZSS-L6, and BeiDou-B3 support to the TW7000 line of surface-mount antennas.

Tallysman® Introduces Embedded Full-Band GNSS Helical Antenna

Tallysman® Introduces Embedded Full-Band GNSS Helical Antenna

Tallysman® Wireless Inc. announces the addition of its first full-band GNSS antenna to its industry-leading line of Helical antennas.

Tallysman Introduces eXtended Filtering to Its Precision Antennas

Tallysman Introduces eXtended Filtering to Its Precision Antennas

Tallysman Wireless is excited to announce new eXtended Filtering (XF) features to the TW3900 series of Accuntena® precision antennas.

Airspan Selects Tallysman Timing Antennas

Airspan Selects Tallysman Timing Antennas

Airspan Networks has selected Tallysman timing antennas for its innovative Cloud-Native, Open Radio Access Network (O-RAN) solutions.

Tallysman Wireless Inc. Is Acquired by Calian Group Ltd

Tallysman Wireless Inc. Is Acquired by Calian Group Ltd

Tallysman Wireless Inc. has been acquired by Calian Group Ltd, a publicly owned Canadian company listed on the Toronto Stock exchange (CGY).

Tallysman®’s TW3972 Triple-Band GNSS Antenna Receives European Rail Certification

Tallysman®’s TW3972 Triple-Band GNSS Antenna Receives European...

Tallysman® is excited to announce that the TW3972 has added European Rail Certification to its already impressive list of qualifications.

Tallysman® Announces Low Profile Rail Antenna

Tallysman® Announces Low Profile Rail Antenna

Tallysman, a leading manufacturer of economical high performance antennas and related products, is pleased to announce the availability of the first of a line o...

Contact Tallysman Wireless Inc.

Use the form opposite to get in touch with Tallysman Wireless Inc. directly to discuss any requirements you might have.








    We'd love to send you the latest news and information from the world of Railway-News. Please tick the box if you agree to receive them.

    For your peace of mind here is a link to our Privacy Policy.

    By submitting this form, you consent to allow Railway-News to store and process this information.

    Subscribe
    Follow Railway-News on LinkedIn
    Follow Railway-News on Twitter