GPS World

Category: Applications

  • 2022 Simulator Buyers Guide

    2022 Simulator Buyers Guide

    In our 11th annual Simulator Buyers Guide, we feature simulator tools, devices and software from 11 prominent companies that aid GNSS receiver manufacturers in product design.

    SPIRENT FEDERAL SYSTEMS OROLIA OROLIA DEFENSE & SECURITY LABSAT
    CAST NAVIGATION IFEN TELEORBIT GMBH WORK MICROWAVE
    QASCOM M3 SYSTEMS JACKSON LABS TECHNOLOGIES SYNTONY

    SPIRENT FEDERAL SYSTEMS

    Alternative PNT, CRPA, M-code & Y-code, Non-GNSS Sensors & Anechoic Chamber Testing

    Alternative RF Navigation Simulator Photo: Spirent Federal Systems
    Alternative RF Navigation Simulator (Photo: Spirent Federal Systems)

    New Alternative RF Navigation Simulator. Authorized users of Spirent’s alternative PNT simulation system can generate alternative RF navigation signals individually or concurrently with GNSS signals.

    GSS9000. The GSS9000 Series multi-frequency, multi-GNSS RF constellation simulator is Spirent’s most comprehensive simulation solution. It can simulate signals from all GNSS and regional navigation systems and has an unrivaled update rate of 2 kHz (0.5 ms), enabling ultra-high-dynamic simulations with accuracy and fidelity. The GSS9000 supports M-code, Y-code, alternative PNT and non-GNSS sensors, and comes with built-in jamming, spoofing and flex power.

    SimMNSA. Spirent Federal has the first fully approved MNSA M-code simulator. Authorized users of the GSS9000 series of simulators will be able to utilize the advanced capabilities of SimMNSA to create robust military GPS user equipment (MGUE) solutions.

    Spirent GSS9000 Series constellation simulator Photo: Spirent Federal Systems
    Spirent GSS9000 Series constellation simulator (Photo: Spirent Federal Systems)

    CRPA Test System. The CRPA Test System is scalable, testing antennas from 4 to 16 elements and beyond. More than 1,000 independent GNSS, jamming and spoofing signals can be generated/simulated across a phase-calibrated precise wavefront.
    SimINERTIAL. Supporting the leading embedded GPS/inertial systems (EGI) and inertial measurement units (IMU), SimINERTIAL enables the controllable generation of inertial sensor outputs, synchronous with simulated GNSS, to test integrated GPS/inertial systems in the lab.

    Anechoic Chamber Testing. Spirent’s GSS9790 multi-output, multi-GNSS RF constellation wavefront simulator system can be used in both conducted (lab) and radiated (chamber) conditions.

    Mid-Range Solutions. Spirent offers solutions for every application and price point. The GSS7000 multi-constellation simulator provides an easy-to-use solution for GNSS testing that can grow with users’ requirements. The GSS6450 RF record-and-playback system enables replay of real-world GNSS tests in the lab.

    [email protected]
    spirentfederal.com
    801-785-1448

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    OROLIA

    Skydel GSG-8 Photo: Orolia
    Skydel GSG-8 (Photo: Orolia)

    Essential to Advanced GNSS Simulator Solutions

    Based on the Skydel GNSS Simulation Engine, Orolia’s advanced and essential GNSS simulators offer a wide breadth and depth of tools to test mission-critical positioning, navigation and timing (PNT) applications and scenarios.

    Skydel Simulation Engine. The highly flexible, high-performance Skydel Simulation Engine transmits GNSS signals in real time to many kinds of software-defined radios. Skydel uses graphics processing units (GPUs) to compute the digital GNSS signal of all simulated satellites, easily scaling from simple to complex use cases. Skydel simulates civil signals from global and regional navigation satellite systems with a 1000-Hz update rate, many kinds of GNSS receiver trajectories with high dynamics, and advanced jamming and spoofing. The Skydel ecosystem also includes features such as open-source plug-ins and API, and the ability to create custom signals. The custom-signal feature allows users to experiment with new signals, such as navigation from low-Earth-orbit satellite systems.

    GSG-8. A scalable software-powered turnkey simulation solution, GSG-8 is configurable to meet virtually any testing requirements. It can support multi-constellation, multi-frequency and hundreds of signals with a 1000-Hz iteration rate. This advanced hardware platform is suitable for space trajectories, custom PNT signals, hardware-in-the-loop, multi-antenna simulation, and more. Encrypted EU signals will be available soon.

    Skydel CRPA Testing. With self-calibration, integrated advanced jamming and spoofing, and the ability to generate thousands of signals, Skydel CRPA test systems provide everything needed to test CRPA systems, with a focus on ease of use and the testing experience from the user point of view. Two flexible configurations, Skydel Anechoic and Skydel Wavefront, have been carefully designed to provide the advanced simulation features required for CRPA testing in a well-thought-out package. Both provide COTS hardware benefits: configuration flexibility and cost-effectiveness.

    GSG-5 and GSG-6. Orolia’s essential simulation platform is a proven, cost-effective simulation solution. Combined with the freely available StudioView software, these simulators provide high-end capabilities in a standalone, portable system that allows operation via a front panel interface. GSG-5 and GSG-6 are available with support for multi-frequency and multi-constellation GNSS signal simulation, pre-built scenarios and test packages, and the features neded to integrate it into ATE systems.

    [email protected]
    www.orolia.com

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    Orolia defense & Security

    BroadSim 4U, Advanced NAVWAR simulations, MNSA and Y-Code (Photo: Orolia)
    BroadSim 4U, Advanced NAVWAR simulations, MNSA and Y-Code (Photo: Orolia)

    Advanced GNSS Simulation for Government & Defense

    BroadSim

    Powered by the Skydel Simulation Engine, BroadSim provides superior NAVWAR performance, sharing the same benefits and key features of its software-defined platform.

    Key Applications

    BroadSim Solo: Multi-GNSS simulations on the desktop. (Photo: Orolia)
    BroadSim Solo: Multi-GNSS simulations on the desktop. (Photo: Orolia)

    MNSA M-Code. BroadSim offers a fully flexible implementation of the Modernized NavStar Security Algorithm, giving you full control over scenario settings with the real encryption used on the M-code signal. Any aspect of your scenario can be changed, such as time, date, location, constellation, downlink data, signal configuration, and visible satellites. It is security-approved by SMC Production Corps and shipping as soon as today.

    CRPA Testing. BroadSim leverages Skydel’s CRPA testing solution to up the ante for demanding NAVWAR scenarios. BroadSim Anechoic allows you to test an entire system as-is. Skydel auto- calibrates the system, maps the antennas, and is designed to streamline chamber setup and reduce hardware. Broadsim Wavefront tests the antenna electronics, prioritizing the ability to have dynamic trajectories and allowing you to model any scenario with an unlimited number of interferences. The system is scalable from 4 to 16 elements, is phase coherent, performs real-time automated phase calibration, and has built-in jamming and spoofing.

    BroadSim Wavefront: Phase-aligned NAVWAR simulator for CRPA (Photo: Orolia)
    BroadSim Wavefront: Phase-aligned NAVWAR simulator for CRPA (Photo: Orolia)

    Advanced Jamming and Spoofing. With Advanced Jamming, users can add ground- and space-based emitters to scenarios, generate an unlimited number of jamming signals on 1 RF output, and simulate flight profiles where interference power levels at the UUT dynamically change depending on the scenario motion. With Advanced Spoofing, users can simulate multiple spoofers simultaneously. Each spoofer can generate any GNSS signal and has an independent trajectory and antenna pattern. Signal dynamics between each spoofer and receiver antenna are automatically determined so no time is wasted.
    More Features. Inertial and alternative RF navigation, built-in Flex Power, real-time performance with ultra-low latency of 5ms, high dynamics, terrain modeling, and RMF STIG compliance.

    [email protected]
    www.oroliads.com

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    LABSAT

    LabSat 3 (Photo: LabSat)
    LabSat 3 (Photo: LabSat)

    Test Anywhere with LabSat 3 Wideband and SatGen Simulation Software

    LabSat 3 Wideband. The LabSat 3 Wideband is a compact yet powerful multi-constellation and multi-frequency GNSS testing solution. The easy-to-use, one-touch record-and-replay function provides an efficient way to test and develop GNSS-based technology without the cost and limitations of live-sky signals.

    It is lightweight and portable, enabling easy collaboration with colleagues by sharing scenario files over the internet, and making it a suitable test partner for remote working. Additionally, the removeable solid-state drive (SSD) of up to 7 terabytes and a two-hour runtime provided by an internal battery is ready for field testing in any environment.

    LabSat 3 Wideband can record and replay up to three different channels at 56-MHz bandwidth across all major constellations and signals, including:

    • GPS: L1/L2/L5
    • Galileo: E1/E1a/E5a/E5b/E6
    • GLONASS: L1/L2/L3
    • BeiDou: B1/B2/B3
    • NavIC: L5/S-band
    • QZSS: L1/L2/L5
    • L-band correction services including SBAS
    • 2x CAN and 4x digital input channels tightly synchronized with GNSS data
    • future signal launches are also supported, including L2C, L5 and L1C

    SatGen Simulation Software. SatGen software allows users to quickly create bespoke, accurate scenarios with their own time, location and trajectory that can be replayed via a LabSat GNSS simulator.

    The latest version of SatGen can be used to create a single scenario containing all the upper and lower L-band signals for GPS, Galileo, GLONASS, BeiDou and NavIC.

    [email protected]
    www.labsat.co.uk

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    CAST NAVIGATION

    Photo: CAST Navigation
    Intuitive graphical interface (Photo: CAST Navigation)

    Accurate, repeatable simulation solutions

    When getting the job done right the first time — and every time — matters, CAST Navigation’s suite of simulator solutions delivers precision, accuracy and repeatability. From simple integration testing to complex mission simulations, CAST Navigation solutions scale to meet user requirements.

    Powered by multi-frequency, multi-constellation GNSS and interference signal-generation technology, CAST Navigation simulators provide coherent, highly accurate and fully programmable signals. Advanced, configurable vehicle trajectory capabilities meet project requirements ranging from antenna testing to simulations of squadrons maneuvering in contested environments.

    Intuitive Graphical Interface. A comprehensive and intuitive graphical interface unifies all simulator capabilities so users can configure complex simulation scenarios quickly. For example, CAST Navigation simulators can model many vehicle types with static and dynamic motion profiles: airborne, terrestrial, aquatic or space-based. Using configured scenario profiles or vehicle truth data, CAST Navigation simulators create high-dynamic, 6-DOF real-time trajectories.

    High-Fidelity Simulations of Real-World Conditions. CAST Navigation solutions can reproduce terrain, sea-state and atmospheric effects to simulate missions with high fidelity. Jamming capabilities recreate natural, urban and hostile interference to produce precisely controlled waveforms with high output power and exceptionally low intermodulation noise.

    Multi-Frequency, Multi-Constellation Simulations. The GPS/GNSS simulators generate accurate, programmable signals to each antenna element with up to 16 satellites in view from as many as four constellation types. GPS simulations can generate any positioning signal (C/A-code, P-code, Y-code, SAASM, M-code AES and M-code MNSA).

    Modular, Scalable Solutions. Proprietary synchronization technology lets CAST Navigation configure customer solutions with multiple simulator capabilities — GPS/GNSS, inertial, jamming, and CRPA — to meet specific project needs. As those needs evolve, these solutions do not become obsolete. Rather than replace a functioning system, customers can rely on modular architecture to meet their new requirements.

    [email protected]
    www.castnav.com
    978-858-0130

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    iFEN

    Photo: IFEN
    NCS NOVA GNSS simulator (Photo: IFEN)

    NCS NOVA GNSS Simulator

    The NCS NOVA GNSS simulator is a high-end, powerful and easy-to-use satellite navigation testing and R&D device. It is fully capable of multi-constellation and multi-frequency simulations for a wide range of GNSS applications. It is one of the leading solutions on the market, providing multiple GNSS frequencies in one box.

    Because of the modern and flexible software-defined radio (SDR) design of this simulator, testing requirements will be met with the minimum of equipment, facilitating logistics and reducing the cost of ownership. The innovative multi-constellation and multi-frequency simulation capability sets new standards in the field of GNSS simulation in terms of fidelity, performance, accuracy and reliability. Designed to deliver maximum flexibility, users are no longer faced with configuration limitations.

    The NCS NOVA GNSS simulator is also able to coherently generate GNSS RF signals on two independent RF outputs simultaneously. The user may freely allocate GNSS signals and RF channels to each of the RF outputs. This feature allows simulation of GNSS signals at two antenna locations simultaneously (this could be two antennas on a vehicle, two separate vehicles maneuvering independently, or a static location plus a mobile unit).

    A new key enhancement to the NCS NOVA GNSS simulator is comprehensive support of new Galileo OS signal message improvements on E1B. By enabling real-time simulation of the Galileo OS message improvements, the NCS NOVA expands a user’s Galileo signal capability.

    In the future, the NCS NOVA also will fully support the new Galileo E1B OS Navigation Message Authentication (OS-NMA) and Galileo E6B High Accuracy Service (HAS) capabilities.

    The NCS NOVA GNSS simulator is the first choice in signal simulation for a wide range of applications including space, aviation, automotive (including autonomous driving testing) and many others.

    About IFEN. IFEN is a leading provider of GNSS navigation products and services. Its technology portfolio includes GNSS RF-signal simulators, GNSS software receivers, simulation and data processing tools. IFEN’s outstanding satellite navigation expertise is provided to customers for services including GNSS system studies, research and development of navigation and integrity algorithms, design and development of GNSS software and hardware, on up to engineering of turnkey facilities and systems.

    [email protected]
    www.ifen.com
    +49-(0)8121-2238-10

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    TeleOrbit GmbH

    MGSE REC/REP 2.0 (Photo: ©Fraunhofer IIS)
    MGSE REC/REP 2.0 (Photo: FhG IIS)

    MGSE REC | MGSE REC-REP 2.0 | MGSE SIM-REP | GNSS DCP Antenna | GOOSE-OSNMA

    The MGSE product family creates a versatile GNSS test and simulation environment that improves the development, qualification and certification process of GNSS receivers within development phases and for validation and certification in end-to-end tests.

    MGSE enables mobile and stationary interference monitoring, for example, for protecting critical infrastructures. It can be used for interference mitigation if combined with TeleOrbit’s GNSSA-6E (six-element antenna array) or its GNSS DCP (dual circularly polarized)antenna.

    With MGSE REC-REP 2.0 users can, among other tasks, record Galileo PRS signals in a real user environment and replay them for Galileo PRS receiver testing.

    MGSE SIM-REP supports the development of software-defined radios/receivers or specialized algorithms by creating a simulation environment that provides the possibility and flexibility to use synthetically generated GNSS data and recorded real-world samples.

    For jamming and spoofing test and evaluation, TeleOrbit offers a sophisticated solution based on the MGSE simulation, recording and replaying product family. For spoofing mitigation, the GOOSE-OSNMA receiver platform is available.

    Technical Background

    The multi-band RF front-end (MGSE REC) receives the GNSS RF signals in different frequency bands simultaneously to obtain digital IF data, which can be used for GNSS multi-system signal analysis and comparison. All GNSS L-band frequencies and the NavIC S-band are supported.

    The MGSE Replay Unit includes a flexible multi-band RF replay device that streams simulated and recorded raw IF data to a digital baseband output or to an analog RF signal. Up to two independent RF channels and up to four GNSS signals (L1, E1, B1, G1) can be provided.

    GOOSE is a powerful yet compact GNSS receiver lab and the rapid prototyping solution for leading-edge GNSS receiver development.

    The GNSSA-DCP (dual circularly polarized antenna) receives RHCP and LHCP signals simultaneously (full L-band). It clearly detects signals which have been corrupted by diffraction and reflections.

    Jürgen Seybold, CTO
    [email protected]
    teleorbit.eu/en/satnav/

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    WORK Microwave

    Xidus Signal Module (Photo: WORK Microwave)
    Xidus Signal Module (Photo: Work Microwave)

    Xidus GNSS Simulator — Modular and flexible

    WORK Microwave’s Xidus is well-known for meeting all requirements regarding multi-GNSS; for its multi-frequency and multi-RF signal generation; for its innovative Signal Extension and Enhancements (SEE) technology; for its advanced customization and configurability; and for world-class remote support with updates, training and even scenario execution.

    Xidus Signal Module

    Compact and powerful, the Xidus Signal Module provides new capabilities of signal generation. Users can perform rigorous and extensive testing of present and future positioning systems when conducting navigation research or developing products.

    • Possible applications: pseudolite generation, massive multipath or navigation signal generation on various orbits.
    • Extensive increase of supported channels: >250.
    • Unlimited number of multipath channels with delay >3,000km.
    • Interference signal generation on up to four independent frequencies.
    • Acts as a software-defined radio (SDR) to replay signals.
    Xidus-648 (Photo: Work Microwave)
    Xidus-648 (Photo: Work Microwave)

    Xidus Hardware Series

    Xidus-424 GNSS Simulator

    • Up to 4 signal modules
    • 2 RF outputs
    • Wide dynamic power range

    Xidus-648 GNSS Simulator

    • Up to 8 signal modules
    • 4 RF outputs
    • 1,000 Hz update rate

    Xidus-Studio Client Software

    Xidus-Studio provides a user-friendly graphical interface to configure any GNSS scenario. Its advanced and outstanding features include:

    • multipath, antenna patterns, jamming/spoofing configuration.
    • logging of simulation output on user-defined IP networks.
    • concurrent user access to the hardware.
    • visualization of shared scenarios on multiple desktop PCs.

    [email protected]
    www.work-microwave.com
    +49-8024-6408-222

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    Qascom

    Photo: Qascom
    Photo: Qascom

    QA707 cyber-security simulator

    QA707 is the cutting-edge solution for global threat GNSS awareness and management. It is a GNSS simulator specifically designed to test cyber-attacks and authentication, and includes the simulation of GNSS interference, deception, jamming, spoofing and advanced cyber-threats such as data- and code-level attacks.

    The high flexibility in the creation of the scenarios and the definition of the type of attacker allow cyber-threat and vulnerability testing for several applications,These applications may include, for example, autonomous driving and vehicle tracking, aeronautics and high dynamics applications, space GNSS receivers and timing.

    OSNMA Support. The Galileo Open Service Navigation Message Authentication (OSNMA) simulation is an opportunity to test the new Galileo data protected service against several known vulnerabilities in GNSS applications. The OSNMA simulator is also available as a standalone tool, allowing the generation of OSNMA data that can be used with third party simulators.

    PC-capable. QA707 runs on a standard PC. It is compatible with several third-party hardware RF up-converters, including National Instruments’ USRP. Additionally, it can support customer-specific hardware through the hardware API interface.

    QA707 Main Features

    • Multi constellation (currently GPS L1, GALILEO E1, SBAS L1)
    • Galileo OSNMA
    • RF simulation, binary file dump, signal record and replay
    • Support to SDR platforms and open API for custom RF upconverters
    • Runtime streaming of scenario information over UDP (motion, channel data)
    • Data level cyber-attacks
    • Accurate spoofing signals control, trajectory spoofing, signal replay attacks
    • Narrow band, wide band, frequency modulated jamming
    • Integrity threats (on request): evil waveform, erroneous ephemerides, code/carrier divergence, low satellite signal power, excessive range acceleration
    • Built-in editing tools: Rinex editor, trajectory editor

    [email protected]
    www.qascom.it

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    M3 Systems

    The StellaNGC All-in-one testing platform. (Photo: M3 Systems)
    The StellaNGC all-in-one testing platform. (Photo: M3 Systems)

    High-end multi-constellation and multi-frequency GNSS Simulator and Record & Playback

    M3 Systems offers a fully integrated all-in-one testing solution for GNSS. Thanks to a versatile SDR approach, StellaNGC provides on a single HW platform GNSS simulation and GNSS record & playback functionalities. It answers user challenges from aerospace, defense, ground transportation and telecommunication fields when testing the PNT functions of their GNSS-based systems.

    StellaNGC Plug & Play. This fully scalable and customizable simulator is based on a layered architecture to provide PNT data to the user at different levels (RF, IQ, GNSS raw data, trajectory).

    Based on COTS platforms from National Instruments (NI), StellaNGC P&P allows the simulation of civil signals from GNSS as well as ground-based and satellite-based augmentation systems. It covers terrestrial, aerial and spatial trajectories (including high dynamics). It also enables assessment of GNSS solution robustness with jamming, meaconing and spoofing capacity.

    StellaNGC P&P Main Features

    • Multi-constellation, multi-frequency GNSS simulation
    • Multi-antenna (CRPA applications) and multi-trajectories
    • Jamming and spoofing simulation
    • Cm-level positioning
    • Low latency HIL simulation
    • SBAS and RTK augmentation systems
    • 3D multipath generation
    • IMU sensors modelization
    • Configuration of all scenario parameters
    • Signal control during run-time
    • Intuitive and easy to use GUI

    StellaNGC Record & Playback. As a complement to simulation, StellaNGC RP allows test and validation of PNT functions through high-fidelity record-and-playback of GNSS signals. It allows recording by selection of a center frequency (65 MHz–6 GHz) or with a predefined list of GNSS frequencies for each of its 4 RF channelw, with a bandwidth of up to 120 MHz.

    StellaNGC R&P Main Features

    • Multi-bands record & playback
    • Programmable center frequency and bandwidth
    • Single or multi-channel (up to 4) simultaneous records
    • Easy-to-use graphical interface
    • Access and command through API
    • Automatic gain control
    • Smart I/Q recording (event-based record)

    [email protected]
    m3systems.eu/en/home/

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    Jackson Labs Technologies (JLT)

    CLAW (Photo: Jackson Labs Technologies)
    CLAW (Photo: Jackson Labs Technologies)

    Miniature simulator and scenario generator

    The 18-channel miniature full-constellation CLAW GPS Simulator is a fully self-contained, low size, weight, power and cost (SWaP-C) miniature GPS simulator. It is very popular in manufacturing environments as well as R&D applications that require consistent and repeatable local GNSS signals at low price points.

    The CLAW simulator does not require external computers for processing and control — it works fully self-contained by simply applying power, and storing location/time/date data in internal non-volatile memory, or by storing complex vector data to simulate highly dynamic scenarios. The CLAW also can be used to transcode NMEA or SCPI position/velocity/time (PVT) data into GPS RF signals. For 2022, JLT added driver support for a large number of additional GNSS front-end receivers when using the hardware-in-the-loop (transcoding) feature of the unit to, for instance, transcode from one GNSS system to another.

    JLT offers an easy-to-use, highly configurable and cost-free SimCon Windows application program that is downloadable from the JLT website. SimCon allows random scenario generation and is thus usable to simulate leap-second events, Week 1023 rollover events, or any other GPS live-sky scenarios, including highly complex yet easy-to-create dynamic vector simulations.

    For authorized U.S. government users, a version that does not have altitude and velocity limitations is popular for low-Earth-orbit (LEO) simulations. Multipath simulation allows use of the entire 18-channel simulator capability.

    The unit can be field-upgraded with an easy-to-use in-field software upgrade feature. The CLAW is also very useful in GNSS receiver sensitivity testing for R&D or mass-production assembly lines as it allows accurate control of RF output power ranging from –100 dBm to less than –130 dBm with 0.1-dB resolution and typically better than 1-dB accuracy over the controllable power range.

    The CLAW GPS Simulator also has a built-in RF signal generator with sweep, CW and random noise functions that are useful in simulating GNSS jamming scenarios, as well as GPS spoofing scenarios. The simulator comes in an FCC-certified metal desktop enclosure with numerous accessories.

    The CLAW firmware has been updated to allow live-sky almanac and ephemerides to be automatically uploaded from various externally connected GNSS receivers. This makes simulations using real-time live-sky constellations (such as used in simulating spoofing attacks) an easy task. A free firmware update is available from JLT.

    [email protected]
    www.jackson-labs.com
    702-233-1334

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    SYNTONY GNSS 

    High-end GNSS simulation solutions for R&D, integration and product testing

    Syntony GNSS specializes in GNSS/PNT software-defined receiver (SDR) technologies, operating from receivers to test and measurements solutions. Its products and solutions address multiple markets and use cases in the space, defense and transportation industries. 

    Constellator. (Photo: Syntony)
    Constellator. (Photo: Syntony)

    Constellator GNSS Simulator. Scalable, cost-effective, and high-fidelity SDR software-based platform supporting multi-constellation signals and frequencies (open, restricted and custom), hundreds of signals at 1-kHz iteration rate at zero effective latency, space trajectories and high dynamics. Multiple upgradable hardware configurations are available. 

    Constellator CRPA. Synchro-phase SDR by design, advanced jamming and spoofing, thousands of signals, 4 to 16 elements. 

    Echo. (Photo: Syntony)
    Echo. (Photo: Syntony)

    Echo Recorder & Replayer. High-fidelity record-and-replay devices characterizing group-delay, scintillation, and jamming and spoofing interference, from space to ground market segments. 

    • 3 RF channels of 200Mhz sampling rate 
    • 16 bit I/Q 
    • Up to 1.6 GB/s write/read speed. 
    SubWAVE manager. (Photo: Syntony)
    SubWAVE manager. (Photo: Syntony)

    SubWAVE GNSS/GPS Coverage Extension. Universal and seamless GPS/GNSS coverage extension for rail, road and mining infrastructures. SubWAVE signals are natively compatible with every GNSS-enabled device, and the solution uses existing telecom infrastructure to broadcast GNSS signals. 

    www.syntony-gnss.com
    [email protected] 

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  • Septentrio: Receivers guide drills despite ionosphere

    Septentrio: Receivers guide drills despite ionosphere

    Photo: Anglogold Ashanti/Flanders
    Flanders uses Septentrio receivers to guide automated blasthole drills, such as at this South African mine run by AngloGold Ashanti. Photo: Anglogold Ashanti/Flanders

    Flanders, a U.S.-based company with expertise in electrical machinery and control systems, has developed its proprietary ARDVARC advanced drill-rig control system to control mine-drilling machines, making them safer and more efficient. The drill rigs equipped with ARDVARC create holes with centimeter precision. This ensures optimal rock fragmentation, simplifying and expediting subsequent jobs such as stone extraction and removal.

    Mines close to the poles or to the magnetic equator, such as those in the Amazon, are challenging for GNSS receivers because they tend to experience the most intense ionospheric scintillations, resulting from rapid fluctuations in the electron density in the ionosphere. These scintillations affect GNSS signals that travel from space to Earth, causing degradation of positioning accuracy or even positioning loss.

    To address this challenge, ARDVARC uses Septentrio AsteRx-U GNSS receivers. They are housed in a tough IP67 enclosure and run Septentrio’s proprietary GNSS+ algorithms including IONO+, which ensures high-accuracy positioning even during ionospheric scintillations.

    ARDVARC’s benefits include a faster drill cycle time, increased drill hole location precision, increased drill-rig component operating life, improved fragmentation and greater operator safety. The system is available in several levels.

    • The Intelli-rig manual control system also delivers data on the position of each blast hole, the machine operation and the drilling conditions; it incorporates mine-planning functionality using the mine’s existing or Flanders’ optional GPS equipment.
    • One-touch converts a manually operated machine to one operated with a single touch, increasing productivity. Once the machine operator positions the drill rig over the desired target, One-touch initiates the automated drilling process, which includes machine leveling, hole collaring, drilling to elevation and angle, rod handling, bit retraction and jack reset.
    • The fully autonomous drilling solution removes the operator from the cab, allowing one operator to monitor multiple drilling operations from a safe distance. The solution increases productivity by enabling drilling during blasting and shift changes. It uses Flanders’ HazCam to monitor the surroundings, preventing the drill from operating in unsafe conditions.
  • Swift Navigation, SolarCleano: cleaning robots keep solar power running

    Swift Navigation, SolarCleano: cleaning robots keep solar power running

    A SolarCleano F1A robot tackles a tough cleaning challenge on a solar farm in Saudi Arabia. Photo:: SolarCleano
    A SolarCleano F1A robot tackles a tough cleaning challenge on a solar farm in Saudi Arabia. (Photo: SolarCleano)

    SolarCleano, based in Garnich, Luxembourg, makes robots that clean large solar panel installations using GNSS receivers and corrections from Swift Navigation. We asked Christophe Timmermans, SolarCleano’s managing director, a few questions about its technology.

    How often do solar panels need to be cleaned?

    For decades, it was believed that solar panels did not need to be cleaned due to their angle to the ground and rain. Nowadays, however, the cleaning of solar panels is widely accepted as necessary to optimize a plant’s return on investment (ROI).

    How much time per sq. meter do your machines take to clean solar panels?

    To provide the fastest possible ROI to our customers, we developed a range of robots to best address the needs of various solar plant layouts. A large utility-scale project with high level of soiling losses in a desert environment will need a very fast and reactive cleaning solution such as our SolarBridge B1, which can clean 24/7/365 fully autonomously. The most suitable solution for a farm rooftop in Germany that needs to be cleaned three to four times a year might be our F1 model, which can clean the equivalent of up to two soccer fields a day. It is designed for rooftops, floating panels and mid-size plants up to 50 MW. While the speed of cleaning is a very important variable, the quality of cleaning is often considered as the driver to performance, which is why we propose different types of brushes depending on the soiling types. Plus, the robot speed can be modified according to the soiling level.

    Why do robots need GNSS receivers to clean solar panels?

    Moving on inclined, wet glass surfaces makes odometry unreliable because robots might occasionally slip. Therefore, GNSS is the most reliable way to continuously monitor their exact position. Our robots also need path planning because they cannot operate randomly like lawn mowers. Safety is obviously a major concern; we need a very high localization accuracy to ensure that robots don’t fall off the panels. Finally, the largest solar plants are developed in dry, remote locations with high irradiation such as the Sahara, Atacama and Australian deserts. GNSS allows us to have very accurate localization even in those remote areas. In addition, this solution can easily be installed on already-existing solar plants with little capital expenditure.

    What spatial accuracy requirements do the robots have for this task?

    Safety is our absolute priority. Therefore, our robots need an accuracy of less than 3 cm. They also need to be aware, in real time, of changes in their surroundings, such as maintenance teams, animals and uneven ground.

    On large solar farms, GNSS receivers always have a clear line of sight to the satellites and do not suffer from multipath. So, what are the key technical challenges?

    Our robots have the additional advantage that they do not need to drive very fast. However, we need to manage fleets of robots on the other side of the world in regions difficult to access and with harsh weather conditions, such as very high or low temperatures and the accumulation of dust behind panels due to air vortices. We need to be able to perform remote maintenance and solve any issue from our control center in Luxembourg. These challenges make our robots increasingly robust. With a current fleet of more than 300 robots around the world, we collect lessons every day to ensure a greater reliability for our upcoming generations of robots.

    Why did you choose to partner with Swift Navigation?

    We share a vision with Swift: “Accessible automated solutions serving sustainable goals.” We also share other important values, such as “iterate quickly” and “focus on what matters.”

  • ComNav Technology: Proving high-tech is not a last resort

    ComNav Technology: Proving high-tech is not a last resort

    ComNav’s high-accuracy PileMaster sped construction of the Aarah Resort in the Maldives. Photo: LANKA Foundation and Piling Services Pvt. Ltd.
    ComNav’s high-accuracy PileMaster sped construction of the Aarah Resort in the Maldives. Photo: LANKA Foundation and Piling Services Pvt. Ltd.

    The construction of the Aarah Resort in the Maldives involved building 64 luxury water villas and 12 beach buildings on a shallow-water area with about 1,400 piles. LANKA Foundation and Piling Services Pvt. Ltd. was able to complete the piling project in only 32 days by using a high-accuracy piling solution from ComNav Technology Ltd.

    The traditional piling approach requires many surveyors to stake out the positions of the piles underwater in advance. Not only is this process labor-intensive, it also creates a real-time problem: even if the coordinates are measured accurately by lofting, the primary coordinate markers are soon out of position due to the movement of the piling machines. The stakeout’s accuracy is also threatened by strong waves, ocean currents and coral reefs. Furthermore, in the subsequent piling process, the piling accuracy is reduced due to artificial aiming. During the whole process, surveyors must work in the water and fix the piles at short range, which is dangerous. For these reasons, the traditional piling approach is a low-efficiency, high-cost and high-risk operation.

    Photo: Google Earth
    Photo: Google Earth

    ComNav’s professional positioning solution for high-accuracy piling provides a 9-inch high-resolution tablet with an integrated GNSS receiver, a T300 GNSS receiver as the base station, and two AT340 antennas with magnetic mounts combined with PileMaster software. Its integrated GNSS receiver tracks GPS, GLONASS and BeiDou signals, enabling the system to work even in challenging environments. The system can acquire real-time kinematic (RTK) corrections via an internal UHF transceiver from the T300 receiver or connect to a local continuously operating reference station (CORS). Moreover, PileMaster is designed with an intuitive interface with clear element-management capability, supporting import of up to 10,000 points from Excel, TXT and CAD formats to meet the specific demands of a high-accuracy piling project.

    Compared to the traditional piling method, ComNav’s intelligent control system for piling is an all-weather, high-accuracy solution with the additional advantages of being widely compatible and easy to manage. Through software system control and real-time processing and display, it can greatly reduce the number of surveyors required on-site. The system can guide users to the location, shorten the construction period, save construction costs, and enable intelligent visualization and monitoring to ensure high-precision construction work.

    After a first successful application in 2017, Foresight Surveyors Pvt. Ltd, ComNav’s local partner in the Maldives, used the solution in many projects, including construction of the Kunaavashi Resort & Spa in 2018 and the Kuda Villingili, Dhigufaru Island and Maniya Faru resorts in 2019.

  • Hexagon: Mining safely with rock-solid technology

    Hexagon: Mining safely with rock-solid technology

    Photo:BeyondImages/iStock/Getty Images Plus/Getty Images
    A mining road-train loaded with ore passes through an outback town. A Hexagon system will guide autonomous movement of similar heavy vehicles. Photo: BeyondImages/iStock/Getty Images Plus/Getty Images

    Hexagon’s Autonomy & Positioning and Mining divisions recently partnered with Mineral Resources Limited (MRL), a mining services company, to develop an automated road-train solution for deployment on MRL’s haulage fleet over the next two years. The solution integrates drive-by-wire technology with an autonomous management system to orchestrate vehicle movement in road-train haulage to improve safety, productivity and sustainability. We asked Lee Baldwin, the director of Hexagon’s Autonomy & Positioning division, a few questions about the system.

    What does an automated road-train do?

    It is for haulage on roads hundreds of kilometers long. It first will be used to move ore from a mine processing facility in the Pilbara region of Western Australia, about 1,200 kilometers north of Perth, to Port Hedland, where it is loaded on ships bound for Asia for use in steel mills. Typically, this is done using either rail or a road train, which is a highway truck pulling multiple trailers. Today, a person drives a road train.

    What motivated this project?

    Mines have difficulty finding drivers for mining trucks and road trains because the mines are very far away from the nearest city, Perth, so they must fly workers in and out, which is very costly. Many of them are on 10-day shifts. Also, there are safety concerns.

    How does an automated road-train work?

    It requires three typical subsystems that you would have on any autonomous vehicle. The first one is positioning, including redundant GNSS receivers with our TerraStar correction services. The second is a perception system for collision avoidance, using our HxGN MineProtect Collision Avoidance System. The third one is route planning. We will start by platooning, with a driver in the first truck, which will be followed by three unmanned ones, each towing multiple trailers. Each truck will have the positioning, perception and route-planning systems. Later, we will achieve full autonomy by removing the driver from the lead vehicle.

    How will the transfer at the mine work?

    At a mine site, the road train will be commissioned in a sequestered area, then sent to a loading area where it will be loaded with ore, either automatically or by a manned wheel loader. Next, it will travel 200 kilometers to the port, where it will dump the ore. Finally, it will be decommissioned and queued up for the return journey.

    Which parts are already in place and which ones are still being developed?

    At Hexagon, we are already putting technology in manned mines. For example, we already have the collision-avoidance system, a fleet management system, and some sitewide planning systems. However, the trucks that the customers are choosing will have to be converted to be drive-by-wire to accommodate our autonomy system. They will use two PwrPak7 GNSS receivers and the TerraStar correction service.

  • Trimble: Grading smooth as butter

    Trimble: Grading smooth as butter

    On a project on the Butterfield Landfill — about 45 miles south of Phoenix, Arizona — Buesing Corp. needed to excavate and haul 1,850,000 cubic yards of dirt from a landfill more than 60 feet deep while grading the slope, basin and stockpile; inserting storm drains; and making an operations layer.

    Buesing, founded in 1965, specializes in modeling and building complex underground systems in challenging conditions. It had four months to complete the initial mass grading, with another month for shaping the stockpile and a final month for the operations layer and piping. The mass grading of the site required an accuracy of plus or minus one tenth of a foot in a landfill with 4:1 slopes and a slope length of 300 linear feet, and the operations layer had to be two feet thick. The project also required installing storm drain inlets, flow lines, and outlets to grade.

    To remain on schedule, the project required moving large quantities of soil quickly and efficiently, as well as adjusting grading models to incorporate design updates and changes while in production. “We used DTMs and orthophotos collected with our UAV to track progress quantities and adjust the stockpile model to minimize haul distances and slope rework as well as maintain proper drainage and control of stormwater,” said Rio Byman, Buesing’s GPS manager, who is responsible for building 3D models and managing the maintenance, calibration and updates for the company’s machine control (MC) solutions.

    Photo: Trimble
    A caterpillar CAT14M3 motorgrader is guided by Trimble’s dual-mast Earthworks system. (Photo: Trimble)

    For this project, the company used heavy equipment both with and without MC, including blades, excavators and dozers with MC, along with GNSS-based grade checkers to control the earthmoving operations. Specifically, Buesing, which started converting its equipment to Trimble around 2018, used the Trimble Earthworks Grade Control Platform and the Trimble GCS900 Grade Control System on the site and Trimble Business Center at its office.

    Buesing works in a variety of market segments for public and private entities in seven states, though it performs most of its work in the Phoenix metropolitan area. Key to its success has been an emphasis on skilled crews, continuous training and technology. In fact, Buesing was one of the early adopters of machine control in 2006. “A decade ago, the technology was pretty rudimentary, which limited adoption,” Byman said. “That’s changed a lot in recent years, particularly in the ease of use and flexibility. Today, grade control is an integral part of the company’s ability to build ever-more-complex solutions in even more challenging site and soil conditions.”

    The company started with the Trimble GCS900 on single-mast and dual-mast blades, excavators and dozers. It has since moved to the Trimble Earthworks Grade Control Platform along with Trimble Business Center for managing 3D models. Working closely with SITECH Southwest, Buesing has gone from six machines with grade control to more than 20 in just five years. The company relies on grade-control solutions on its excavators, dozers, motor graders and scrapers, and has used them on projects of every scope and scale, though their value is most evident on urban high-rise excavation.

    “It takes time for operators to gain faith in the data, and know that the machine will excavate efficiently and accurately, whether building pads or cutting basements,” Byman said. He believes that improved productivity in the field comes with trust in the technology.

    Using Trimble Earthworks’ Autos mode, the software controls the implements while the operator controls the machine’s direction and speed for consistent, high-accuracy finished grade in much less time than it would take without automation. “On any jobsite, the operators have to be aware of everything around them, as well as what’s going on with the blades or scrapers,” Byman said.

    “With Autos, they’re able to focus on what’s going on around the job and plan for watering and other environmental conditions with confidence that the machine is digging to grade. This makes our jobsites more productive, safer and more efficient. We have happier operators who are excited to come to work with newer equipment.”

  • Toughen GPS to resist jamming and spoofing

    Toughen GPS to resist jamming and spoofing

    By Bradford W. Parkinson
    Aeronautics and Astronautics Professor Emeritus (recalled)
    Stanford University

    Brad Parkinson
    Brad Parkinson

    We, of the PNT universe, have been hearing a rather continual message of doom from the media regarding the fragility of the GPS (or GNSS) signals. In a way, they are right. The received GPS signal is 1/10th of 1 millionth of 1 billionth of a Watt. It can be susceptible to jamming and spoofing.

    In response, the U.S. government has sponsored major studies and some competitive tests of techniques to augment or possibly replace GPS. I applaud such queries, but also would strongly advocate more balance in efforts to increase robustness of positioning, navigation and timing (PNT).

    Specifically, I argue for increased emphasis on well-known techniques that can greatly toughen GNSS receivers to both jamming and spoofing. Some of these techniques are deliberately denied to civil users by government policy.

    Background

    The PNT Advisory Board (PNTAB) is a panel of national experts who report to the PNT ExCom. The ExCom is comprised of the deputy heads of the nine U.S. government departments with the largest stakes in PNT. The PNTAB has a starkly simple and well-stated goal:

    To meet its overarching goal, the PNTAB has developed a three-legged strategic framework, known as “PTA”: “We must protect, toughen and augment GPS to ensure that it continues to provide economic and societal benefits to the nation.”

    Most current U.S. government efforts have been focused on the third of the PNTAB strategic legs: augmenting the GPS system. These system augmentations include: modernized Loran (eLoran), fiber-optic distribution of time, and ranging to low-Earth-orbit (LEO) satellites (particularly the swarms of communications satellites). In general, these system augmentations offer no hope of being equivalent to GPS in terms of availability and accuracy.

    However, augmentations have the advantage of either being less vulnerable to interference, or highly proliferated in case of satellite outages. As supplements, or in an emergency, they can perform a very valuable role, but with nowhere near the equivalent performance of normally operating GNSS, which can routinely provide worldwide, 24/7 precisions better than decimeters in the dynamic real-time kinematic (RTK) mode. In the United States, GPS also offers continuous, real-time integrity assessments courtesy of the FAA1. Europe has a similar, compatible integrity system called EGNOS, and there are other regional system augmentations.

    In summary, the current PNTAB assessment regarding these substitutes is:

    “No current or foreseeable alternative to GNSS (primarily GPS) can deliver the equivalent accuracy (static down to millimeters) and worldwide, 24/7 availability.”

    Toughening User Equipment

    Toughening, the second leg of our assurance strategy, includes all aspects of GPS enterprise vulnerability — satellites, ground control and user equipment. For this article, I am focused on toughening the user equipment. I would argue that we have largely under-emphasized, or been prohibited by national policy from using, well-known and widely available user equipment toughening technology.

    The main vulnerabilities of GPS receivers are jamming and spoofing of the received signals. Familiar anti-jam (A/J) methods can substantially overcome the inherent weakness of GPS signals to defeat deliberate jamming and spoofing. As I outline here, such measures can reduce a jammer’s effective radius by a factor of more than 100 and reduce the effective jammer area by a factor of 10,000 compared to the unprotected receiver.2

    Thus, these methods are also deterrents, because they can render ineffective such hostile (or possibly inadvertent) acts. Further, the technology that provides this significant toughening is available now or will be within a few years, rather than the many years required by some alternative, system-level augmentations.

    Toughening techniques (A/J improvements) are traditionally calibrated as the improvement in the amount of jamming that can be tolerated, measured by the jamming-to-signal power ratio (J/S) expressed as decibels (dB). However, for this discussion, I will also use a different, more intuitive, measure. This metric is the Denial Radius Reduction Ratio (DRRR):

    DRRR = (radius of jammer denial after J/S measure applied)/(jammer radius without improvements)

    For example, a 15-dB improvement in J/S would lead to a DRRR of 0.178.3 In other words, the 15-dB improvement has reduced the denial radius to about 18% of the line-of-sight radius that would be denied to an untoughened receiver. Note that the simultaneous use of techniques is generally multiplicative. For example, simultaneously applying technique #1 with a DRRR1 of 0.5 and technique #2 with a DRRR2 of 0.3, would result in a DRRR1&2 of 0.3 *0.5, or an overall DRRR of 0.15. This is the advantage of using this metric to describe the A/J improvements. 4

    Baseline Case

    For our basis for comparison, we will consider the L1 C/A signal in full accuracy (State 5) tracking mode and a 1-kW noise jammer.5,6 For this situation, the line-of-sight jammer could deny GPS to a radius of about 560 kilometers. A discussion of the lower accuracy State 3 tracking is included below.
    It is useful to consider toughening techniques in four major categories.

    Toughening Category 1: Signal Processing. With L1 C/A, GPS receivers can improve jamming resistance, albeit with loss of ranging (tracking) accuracy, by using code tracking mode – State 3. This reduces a line-of-sight jammer’s denial radius (DRRR) to about 0.29 (a 10.7 dB improvement).

    Toughening Category 2: Inertial Components and Very Stable User Clocks. This includes miniature micro-electromechanical (MEMS) components up to high-grade inertial measurement units (IMUs) and quartz to chip-scale atomic clocks (CSACs). These techniques enable narrower tracking filters and longer averaging, as well as allowing navigation through regions when GPS is denied. The range of DRRRs is 0.40 down to 0.10. We will use a nominal value of 0.18 (a 15-dB improvement).

    Toughening Category 3: CRPAs. Controlled reception pattern antennas (CRPAS) are digital, multi-element, phase-steered antennas. They represent well-understood and available technology; they have been used in large surface-search radar systems for many decades.7 They can be used in null-steering or beam-steering modes.8 The number of antenna elements could range up to dozens. Potentially, they could produce DRRRs down to .01 — that is, a 99% reduction of jammer radius to 1% of the unprotected GPS receiver value.

    Unfortunately, the U.S. government does not allow more than three-element CRPAs to be manufactured or sold for civil use. 9 This is due to some very old International Traffic in Arms Regulations (ITAR). For our nominal example, we will assume the restriction has been relaxed and use a CRPA of about 20 elements, which should produce a DRRR of 0.06 (a 25-dB improvement).

    Toughening Category 4: Signal Alternatives. This category includes alternative modulations at 1575 MHz (L1C, Galileo or other GNSS) and alternative frequencies (L5, L2, Galileo). Note that the modern signals generally offer significantly improved signal-processing toughening as well as increased power.

    Using L1C in State 3 compared to L1 C/A in State 5 would yield a DRRR of 0.10. (a 20.3-dB improvement). The L1C international signal should be operational on GPS by mid-decade. The L5 signal, at 1176 MHz, is clearly the most capable of the civil GPS signals in terms of jam resistance. L5 also should be declared operational by mid-decade. As the use of LEO communication satellites matures, their use may also fit this category.

    Summary of Receiver Toughening Options. Quantification of the selected, nominal receiver augmentations are summarized in FIGURE 1 for both full accuracy (State 5, centimeter-level accuracy in RTK) and for less accurate code tracking (State 3, meter-level accuracy). These results are shown with a logarithmic scale to accommodate the wide range of denial radii.

    Figure 1. Effect of receiver augmentations on accuracy for both State 5 and State 3. (Image: Brad Parkinson)
    Figure 1. Effect of receiver augmentations on accuracy for both State 5 and State 3. (Image: Brad Parkinson)

    The example shows that a 1-kW hostile jammer’s denial radius10 can be reduced by a factor of about 100, using the conservative example augmentations of inertial and CRPAs. Because area is proportional to radius squared, the effective denial area of an augmented receiver would be 1/10,000th of the unaugmented receiver, using the example values.

    Reverting to code-only (State 3) tracking, it enables operating through higher levels of jamming, albeit with less ranging precision. All these receiver augmentations and tracking techniques would also offer a significant defense against any attempt to spoof (deceive) the position measurement. Again, none of these techniques are new; we demonstrated the capabilities at the original GPS Joint Program Office in 1978, more than 40 years ago. Today, many competent manufacturers are offering toughened GPS receivers with combinations and variations of these techniques.

    GPS jamming tests at White Sands have caused aircraft interference, which could be largely avoided with toughened receivers. Here, M-code is tested on Joint Light Tactical Vehicle platforms in 2020. (Photo: Joe Bullinger/U.S. Navy)
    GPS jamming tests at White Sands have caused aircraft interference, which could be largely avoided with toughened receivers. Here, M-code is tested on Joint Light Tactical Vehicle platforms in 2020. (Photo: Joe Bullinger/U.S. Navy)

    Meeting Increasing Threats

    Threats of both jamming and spoofing seem to have accelerated. Devices to perform these illegal acts are freely advertised on the internet. In fact, we read of incidents both in the United States and abroad.11 Near White Sands Missile Range in New Mexico, there have been GPS air traffic control outages due to authorized military operational jamming exercises. Such interruptions could be largely avoided if more robust (toughened) GPS receivers, with the enhanced jam resistance techniques outlined here, were in use.

    News reports also highlight the spoofing issue. Hardening against this threat is also a task for toughening. A serious spoofing sequence usually starts with a strong jamming signal to cause the user’s receiver to break lock, followed by a strong false GNSS signal that causes false lock by the receiver. Using the false signal leads to a false position, of course. The first line of defense is to avoid the break-lock threat. Failing this, numerous self-check and authentication schemes can be used to avoid false positions.

    A conclusion is that avoiding the break-lock jamming is a first line of defense against a spoofing attack. Of course, the toughening techniques to avoid this are the main subject of this paper. One well-known expert has stated that, for a well-designed receiver, a spoofing attack might deny the measurement of position, but should never cause false PNT. I will leave further discussion of spoofing to other authors.
    Returning to disruptions of service in general, some have suggested many interference occurrences have gone unreported, because the typical user would not know where to make such a report. To remind the reader, the official reporting center is online at www.navcen.uscg.gov/?pageName=gpsUserInput.

    In addition, the U.S. Federal Communications Commission (FCC) has repurposed a portion of the spectrum adjacent to the main GNSS L1 frequency (1575 MHz). The agency is converting the license holder’s original authorization to transmit a weak space-transmitted signal into a much stronger terrestrial system, potentially with thousands of transmitters. Extensive testing of civil GPS receivers by the U.S. Department of Transportation demonstrated that the planned repurposing will interfere with many existing receivers. Some observers call this disruption “legal jamming.”

    Such a new spectrum use could have grave impacts on those existing receivers, notably aviation (especially helicopters and UAVs) and first providers. On the other hand, installing toughened replacement receivers would make the users virtually immune to this threat.

    So, this begs the question: If the receiver toughening techniques are so effective, why are they not more prevalent?

    Barriers to Adoption

    Let’s examine the potential resistance to more extensive use of receiver augmentations.

    Knowledge. This involves underestimating the threat to PNT and not understanding that toughening techniques are available. As mentioned above, threats to the fragile GNSS signals are growing.

    There seems to be little interest in the U.S. government to monitor and suppress interference in the United States. Internationally, the reported incidents continue to increase.12 It is also reported that certain European aircraft manufacturers have installed advanced, deeply integrated inertial systems with civil GNSS receivers to defeat or “flywheel” through radio-frequency threats (particularly in the Middle East).

    As this threat trend continues, GPS manufacturers and users must realize that many of these solutions will take time to authorize, implement and install. It appears that the media are not aware that not only are the toughening techniques outlined here feasible, but many manufacturers have product offerings that address these threats. Having off-the-shelf solutions will give the PNT user the opportunity to retrofit and defeat such threats.

    Cost. The cost for a receiver to revert from State 5 to State 3 is zero, and all receivers that use Code 5 (for example, RTK) would naturally have this built in. Regarding use of other frequencies (such as L5) and modulations (L1C) rather than the original L1 C/A, there is some small cost associated, including the additional antenna for L5. Note that all modern cellphone chips, such as Qualcomm’s, have this capability — including integrated carrier-phase measurements — in a chip that is estimated to cost about $5. A potential barrier is that the L5 and L1C signals are not yet declared operational, but these newer GPS signals should be operational within about five years.

    The costs of many inertial components (accelerometers and gyros) have plummeted in the last few decades with the proliferation of MEMS devices, particularly into cellphones and automobiles. Their power consumption has also decreased while their performance has steadily improved. Full IMUs are much more expensive, but are already installed on many commercial aircraft. Robust toughening with inertial sensors can be achieved, but requires deep integration and careful engineering.

    Depending on their complexity, CRPA antennas can be a costly receiver augmentation. Very high-speed (330 MHz is available), 16-bit, A-to-D converters are at the heart of most of these phased-array devices. Some are priced at about $150 each. Applications with a high premium for PNT availability in the face of interference — such as commercial aircraft and cargo ships — should find them affordable. Aircraft manufacturers have resisted retrofitting existing aircraft with larger diameter CRPA antennas because of costs. For some of these applications, integration costs can be more than the costs of the receiver itself, particularly if not included in the original manufacture.

    As the yearly sales of fully toughened receivers increase, the economies of scale should significantly reduce unit costs. Each application will make its own determination of affordability, based on risk.

    Government restrictions. Civil use of CRPAs with four or more elements is restricted by ITAR. These are well-meaning restrictions on technologies that could be used against the United States by hostile military forces. Unfortunately, the phased-array antenna techniques are not only well understood and tested, but relatively inexpensive components are widely available on the open world market. In particular, the restriction on the number of CRPA elements for civil use should be completely removed. All potential enemies are well aware of the beam-steering method and have ready access to the parts to build them. Thus, the restriction is only harming civil users without affording any apparent improvement in general military posture.

    Certified aviation receivers need approval for deep integration of inertial systems and multi-element CRPAs. (Photo: JasonDoiy/iStock/Getty Images Plus/Getty Images)
    Certified aviation receivers need approval for deep integration of inertial systems and multi-element CRPAs. (Photo: JasonDoiy/iStock/Getty Images Plus/Getty Images)

    Gaining permission: FAA flight certifications. To be used in commercial aircraft operations, navigation equipment must be certified by the U.S. Federal Aviation Administration (FAA). Current, certified GPS aviation receivers have rudimentary toughening techniques, but gaining approval for deep integration of inertial systems and multi-element CRPAs must be completed. It is gratifying to hear that work is underway to do this.

    Any civil solution for the United States must expand integrity monitoring beyond GPS to include all GNSS, and must be operationally included in the FAA’s integrity monitoring with WAAS.

    Recommendation

    In describing resistance to interference, I have introduced the idea of DRRR – Denial Radius Reduction Ratio. Also, I have used a 1-kW white-noise jammer as a standard threat for calculating the denial radius of various GPS receiver configurations. My recommendation is that equipment manufacturers specify their receiver offerings by stating their equipment’s denial radius against a “standardized” 1-kW EIRP white-noise jammer.

    Summary

    Media reports of interference to GPS may be accurate, but they generally do not recognize that available toughening techniques can largely defeat those interference threats. While exploring systems-level replacements or augmentations (such as LEO ranging or Loran) is worthwhile, GPS (or GNSS) still offers the greatest capability in combined terms of accuracy, integrity and coverage.

    The goal of all PNT providers — GPS operators, certifiers and manufacturers — should be assured PNT, with the expected accuracy and availability. The described toughening techniques to do that have been known for decades, but have not been generally adopted by many critical civil users. Many manufacturers do offer civil products under existing government constraints.

    The purpose of this article was to describe and advocate the solutions available to increase the robustness and toughening of civil GPS receivers. For example, readily available toughening augmentations for civil receivers can reduce the denial radius of interference by 99% or more. This implies that any denied area would be squeezed down to 1/10,000th of that experienced by an unaugmented receiver.

    The payoff is high, and should be affordable to many high-end, safety-of-life users. Therefore, a renewed focus on toughening of GPS receivers is overdue. We discussed barriers to rapid adoption but, more than the specifics, it is crucial to fully and urgently embrace the goal of toughening receivers, particularly removing the ITAR restriction on antennas.

    Opinions expressed in this article are those of the writer and should not be construed as the official position of the PNTAB or any U.S. government organization.

    Notes

    1. While not a part of the U.S. Department of Defense’s GPS operation, the FAA’s integrity signal (WAAS) is a GPS-type signal directly available and being used by almost all modern GPS receivers, including cellphones.

    2. This is the ration of Denial Radius between, for example, unaugmented L1 C/A in State 5 and augmented L1C in State 3. Please see later footnote and graph.

    3. Calculated as 10 (–15/20)

    4. Of course, the more traditional dB measure of jammer resistance can (in most cases) be simply summed to estimate the total effectiveness. The use of DRRR gives a more intuitive calibration, particularly for non-technical persons who may not be at all familiar with dBs.

    5. State 5 is the tracking mode that provides full accuracy; it requires tracking both the PRN code and the reconstructed carrier. It is required for RTK positioning, which is usually used for automatic control of machines or vehicles. It is most vulnerable to interference. Less vulnerable is State 3 tracking, which only provides code tracking, with precisions of perhaps a few meters.

    6. Deliberate jamming using “matched spectrum” GPS-like modulations have also been employed in the Middle East. The toughening techniques described are also generally applicable, with appropriate rescaling. The matched spectrum is fundamentally used to improve the jammer spectrum efficiency.

    7. See Michael Jones, “Anti-jam systems: Which one works for you?”, posted on gpsworld.com on June 14, 2017, for a survey of manufacturer offerings at that time. Named companies generally continue to offer improved, jam-resistant products. 

    8. Phased-array antennas, by their nature, distort phase and would probably have to be calibrated for precise operations such as RTK. Fortunately, we understand that this problem has been reportedly addressed and largely solved by the U.S. Navy’s JPALs program.

    9. See U.S. Munitions List at www.ecfr.gov/current/title-22/chapter-I/subchapter-M/part-121.

    10. The denial radius results shown can be easily scaled for weaker or more powerful jammers. The scaling goes as simply the square root of the power ratio of a different size jammer to the 1-kW example. A 10-watt jammer is 1/100th the power of the example. The denial radius would then be one tenth of the example, which is the square root of 1/100.

    11. “Ships have reported an increasing number of cases of significant GPS interference and jamming in recent months. The geographic areas with more than one reported incident include the eastern and central Mediterranean Sea, the Persian Gulf, and multiple Chinese ports.” (Source: www.gard.no/web/updates/content/30454065/gps-interference-and-jamming-on-the-increase).

    “North Korea is using radio waves to jam GPS navigation systems near the border regions, South Korean officials said. The broadcasts have reportedly affected 110 planes and ships and can cause mobile phones to malfunction.” (Source: www.bbc.com/news/world-asia-35940542).

    12. “Reports of GPS outages submitted by pilots from the cockpits of commercial flights show that disruptions to the navigation system, which was created and is maintained by the U.S. government, are now standard occurrence on the flight routes between North America and Europe and the Middle East, according to data from the European Organization for the Safety of Air Navigation, known as Eurocontrol.” Fortune Magazine, Nov. 1, 2020.

  • Research Roundup: Lunar GNSS applications

    Research Roundup: Lunar GNSS applications

    Artist's rendering of the Lunar Pathfinder. (Image: SSTL)
    Artist’s impression of the Lunar Pathfinder satellite built by Surrey Satellite Technology Ltd. (SSTL) that will provide communications and navigation services for the Moon.

    NASA and its international partners are planning a return to our natural satellite. The following three papers — presented at the Institute of Navigation (ION) GNSS+ conference Sept. 20–24, 2021 — discuss the role of GNSS in lunar exploration. The full papers are available at www.ion.org/publications/browse.cfm.

    Using GPS for Time Transfer

    NASA and the European Space Agency have conceptualized the initial framework for a GPS-like constellation for the Moon, which will ensure uninterrupted navigation and communication services for future lunar missions. The authors designed a smallsat-based Lunar Navigation Satellite System (LNSS) with time-transfer from Earth-GPS to alleviate the size, weight and power (SWaP) and timing stability requirements of the onboard clocks. A timing filter corrects the lower grade clock when Earth-GPS signals are available and propagates these clock estimates forward in time when no Earth-GPS signals are available. The authors analyzed their proposed time-transfer technique using high-fidelity simulations of an LNSS satellite with an onboard chip-scale atomic clock for three cases of elliptical lunar frozen orbits.

    Bhamidipati, Sriramya, Mina, Tara, Gao, Grace, “Design Considerations of a Lunar Navigation Satellite System with Time-Transfer from Earth-GPS,” https://doi.org/10.33012/2021.18021

    GNSS Nav for Moon Missions

    The authors show the potential of autonomous GNSS signal-based navigation for a set of Moon scenarios. This technology could be a game changer for the future of lunar exploration, representing an extremely low cost and effective alternative for Moon navigation. Results show that not only autonomous GNSS navigation for lunar orbiters is possible, but it also delivers good navigation performance. In fact, navigation with root-mean-square (RMS) errors on the order of 50–100 meters were obtained for scenarios of high interest, such as for the planned Lunar Pathfinder and near-rectilinear halo orbit of the Lunar Gateway space station around the Moon.

    Mangialardo, Marco, Jurado, María Manzano, Hagan, David, Giordano, Pietro, Ventura-Traveset, Javier, “The full Potential of an Autonomous GNSS Signalbased Navigation System for Moon Missions,” https://doi.org/10.33012/2021.18040

    Finding the best lunar orbit

    A continuous and reliable lunar positioning and timing system, such as a GNSS-like constellation, is considered essential infrastructure for lunar exploration. The authors focus on halo orbits with the aim of defining an optimal halo constellation for supporting and delivering a navigation service on the Moon. This paper shows the performance of a GNSS-like constellation deployed in Halo orbits around Earth-Moon L1 and L2 collinear libration points. Different phases have been considered, from a minimum number of satellites able to provide a local PNT service on the South Pole (Initial Operational Capability), to a final, extended constellation able to cover the whole lunar surface (Final Operational Capability).

    Musacchio, Daniele, Iess, Luciano, Carosi, Mattia, Capolicchio, Jacopo, Eleuteri, Massimo, Stallo, Cosimo, Di Lauro, Carmine, “Design of Earth Moon Halo Orbits for a Global Lunar PNT Service,” https://doi.org/10.33012/2021.18020

  • Eos Positioning Systems announces Eos Laser Mapping for Android

    Eos Positioning Systems announces Eos Laser Mapping for Android

    Professionals can capture high-accuracy laser offsets directly into ArcGIS Field Maps on Android devices with Arrow Series GNSS receivers

    Image: Eos Positioning
    Image: Eos Positioning

    Eos Positioning Systems Inc. announces the release of its Eos Laser Mapping for ArcGIS solution on Android devices. Previously, the free solution was available only on iOS. It allows mobile crews to capture asset locations from a distance with survey-grade accuracy.

    “We are excited to provide this already popular iOS solution also to our customers using Android devices,” Eos Chief Technology Officer Jean-Yves Lauture said.

    The solution combines technology from geographic information system (GIS) provider Esri, laser rangefinders from Laser Tech, and Eos’ own Arrow Series GNSS receivers.

    “The Eos Laser Mapping solution was extremely well-received with its initial release, so we are excited to see the same features now available for ArcGIS Field Maps users on Android devices,” Esri Field Apps Engineering Lead Jeff Shaner said.

    The Eos Laser Mapping release on Android supports three workflows, or mapping methodologies: Standard Laser Offset (sometimes called Range-Azimuth), Range-Range (or Range-Intersect), and Range-Backsight (a total station-like method).

    The original laser offset solution was released in 2018 by Eos in partnership with Esri and Laser Tech.

  • Satelles and NIST team up on precision timing

    Satelles and NIST team up on precision timing

    Cooperative agreement expands precision timing distribution options for critical infrastructure and verifies STL’s agreement with UTC via UTC(NIST)

    This March 30, 2022, chart of Satelles and NIST testing verifies that STL timing agrees with UTC. (Chart: Satelles)
    This March 30, 2022, chart of Satelles and NIST testing verifies that STL timing agrees with UTC. (Chart: Satelles)

    Satelles Inc., provider of highly secure satellite-based time and location services, has entered a cooperative agreement with the U.S. National Institute of Standards and Technology that directly connects STL’s operational infrastructure to the source of UTC(NIST), the national standard for time and frequency in the United States produced in coordination with the U.S. Naval Observatory.

    The agreement calls for Satelles to provide its STL service to NIST. Reciprocally, the agreement includes the introduction of a connection between an STL Ground Monitoring Station (GMS) provided by Satelles to the NIST collection of extremely accurate atomic clocks that maintains the official time scale for UTC(NIST).

    The Cooperative Agreement was described in NIST Technical Note 2187, “A Resilient Architecture for the Realization and Distribution of Coordinated Universal Time to Critical Infrastructure Systems in the United States,” published in November 2021.

    In February 2021, Satelles delivered and configured an STL GMS at NIST’s Time and Frequency Division in Boulder, Colorado. This facility is home to the ensemble of high-precision cesium beam and hydrogen maser atomic clocks that maintains UTC(NIST).

    After conducting a series of successful preliminary tests in the spring of 2021, NIST then directly connected the STL GMS to its primary clock ensemble in June 2021. Comparing timing provided by STL to UTC(NIST), the testing confirmed STL’s long-term stability of better than 25 nanoseconds with short-term time deviation of 50 nanoseconds.

    STL from Satelles is a resilient, alternative PNT service from low-Earth-orbit (LEO) satellites that enterprise customers rely on as a primary timing source. Telecom operators, for example, use STL for 5G wireless network deployments where GPS is unavailable indoors or when other timing solutions cannot provide the required level of accuracy.

    STL’s agreement with UTC also is important for critical infrastructure and other applications that require an essential contingency capability to protect the operations of PNT-dependent systems and ensure survivability and resilience.

    “Satelles has a network of GMS nodes positioned around the world to receive STL signals and calculate the position and timing of the satellites for purposes of producing timing corrections, and
    now we are fortunate to have a GMS connected inside NIST’s main time lab,” said Gregory Gutt, president and CTO of Satelles. “It’s an honor to be given direct access to UTC(NIST), especially in an arrangement that delivers benefit to both our customers and NIST.”

    Visit satelles.com/nist for more information about NIST reports that detail the performance of STL and collaborations between Satelles and NIST.

  • eSurvey provides GNSS receivers, rugged handhelds

    eSurvey provides GNSS receivers, rugged handhelds

    eSurvey is a specialized manufacturer of GNSS receivers and rugged handheld collectors founded in 2018 and part of the UniStrong Group. Based in Shanghai, eSurvey is serving OEM and survey companies throughout North America, as well as many other countries.

    “We deliver our products to more than 50 countries, but we are relatively unknown in North America, where we are looking to develop long-term partnerships,” said Jorge Visoso, International Sales Manager. He said the company is prepared to furnish demonstrations to any interested party.

    The name “eSurvey” was inspired by the philosophy of making the surveying job easier by using the best technologies, according to Visoso. eSurvey also aspires to be the confluence between high value and affordable cost.

    The E800 high-precision receiver. (Photo: eSurvey)
    The E800 high-precision receiver. (Photo: eSurvey)

    As the international brand of the UniStrong products, eSurvey leverages the resources and the expertise of a family of companies with many years of accumulated experience. One strength of the company lies in its significant research and development advantages.

    In contrast to many competitors that only supply receivers, eSurvey has a footprint in the entire value chain and is one of the few manufacturers with its own boards and chips, which translate to a more stable supply and reliable quality, Visoso said.

    The company’s portfolio of GNSS receivers is highly diversified. Several models have been highly successful in South Korea and Poland, where the brand has become well known over the past years.

    The most advanced and comprehensive eSurvey receiver is the E800 model, a multi-constellation and multi-frequency receiver with a micro-electromechanical (MEMS) dynamic tilt system and a 5-watt internal radio. Various engines available for this and other receiver models.

    SurPad4.2 software for surveyors. (Photo: eSurvey)
    SurPad4.2 software for surveyors. (Photo: eSurvey)

    eSurvey also offers its own surveying and mapping software, SurPad4.2. SurPad4.2 provides multiple operation and communication systems, has MAP and CAD functions, and has a coordinate system. It also includes a survey mode encompassing TOPO, Control, Quick Point and COGO.

    Besides GNSS receivers, the company supplies precision agriculture and machine control systems as well as USV and UAV systems, which are now selling in markets such as Turkey and Spain.

     

  • Satellites around the Moon take another step closer

    Satellites around the Moon take another step closer

    Artist's rendering of the Lunar Pathfinder. (Image: SSTL)
    Artist’s impression of SSTL’s Lunar Pathfinder satellite that will provide communications services around the Moon. (Image: SSTL)

    News from the European Space Agency (ESA)

    ESA is going to the Moon — in collaboration with its international partners — and seeks to build a lasting lunar link to enable sustainable space exploration.

    The agency has now evaluated initial ideas to create a network of lunar telecommunications and navigation satellites.

    Creating a commercial telecommunications and navigation service for the Moon will allow many of the dozens of planned lunar missions to share the same infrastructure to communicate with Earth, as well as to find their way on the lunar surface.

    The service is needed because the planned missions are becoming regular trips to Earth’s natural satellite rather than one-off expeditions.

    Using a shared telecommunications and navigation service will reduce the design complexity and weight of individual missions, making them more cost-efficient.

    Lowering the ticket price to lunar exploration could also empower a wider group of ESA member states to launch their own national lunar missions, inspiring the next generation of scientists and engineers.

    Call for Ideas

    The call for ideas for how to use a lasting link with the Moon is open until April 30. People working for commercial companies, universities or governmental organizations are welcome to suggest how they would like to use a lunar communications and navigation service.

    This diagram presents a notional preliminary top-level system concept for a lunar communications and navigation service. (Image: ESA)
    This diagram presents a notional preliminary top-level system concept for a lunar communications and navigation service. (Image: ESA)

    Concept Reviews Completed

    Two consortia of companies have now completed their system concept reviews, which set out how to create the lunar constellation, under ESA’s Moonlight initiative to identify the best way to create a lasting link with the Moon. The reviews set out the business and technical analysis needed to identify and justify a number of feasible system concepts for creating the lunar network.

    The next step will be to define a detailed system architecture and identify the most suitable partnership models between private space companies and ESA.

    Telespazio leads the first consortium. The consortium includes:

    • satellite operators Inmarsat and Hispasat
    • manufacturing companies such as Thales Alenia Space Italy, OHB System in Germany and Canadian space technology company MDA
    • Italian Aerospace Logistics Technology Engineering Company (ALTEC)
    • small and medium-sized enterprises such as Nanoracks Europe and Argotec
    • universities and research centers such as SEE Lab, SDA Bocconi and Politecnico di Milano.

    The second consortium is spearheaded by Surrey Satellite Technology Limited, both in the service prime capacity through its lunar services brand SSTL Lunar and as the satellite manufacturer. The consortium includes:

    • satellite manufacturer Airbus
    • satellite network providers SES, based in Luxembourg, and Kongsberg Satellite Services, based in Norway
    • the Goonhilly Earth Station in the UK
    • British satellite navigation company GMV-NSL.

    Artemis Program and Pathfinder

    NASA’s Artemis program will use several of ESA’s service modules to return humans to the Moon, including the ESPRIT communications module for the lunar Gateway’s living quarters for astronauts. With its European industrial partner, ESA is helping to build the Lunar Pathfinder, showcasing lunar communications service provision by providing initial services to early lunar missions, including a complete lunar navigation in-orbit demonstration.

    The Moonlight initiative builds on both the ESPRIT communications module and the Lunar Pathfinder.

    Infographic: ESA
    Infographic: ESA