On Nov. 15, the European Union Agency for the Space Programme (EUSPA) opened the Galileo Open Service Navigation Message Authentication (OSNMA) Public Observation test phase for the secured signal.
The OSNMA is a freely accessible data-authentication function for the Galileo Open Service worldwide. OSNMA provides receivers a first-level of protection against spoofing the Galileo Open Service, assuming that the receiver meets requirements. This is realized by transmitting authentication-specific data in previously reserved fields of the E1 I/NAV message.
Galileo OSNMA improves confidence on the user side by enabling the user to verify the authenticity of the Galileo navigation parameters required for positioning, navigation and timing. In particular, it will allow the user to authenticate geolocation information of the Open Service:
the ephemerides and clock corrections
the ionospheric corrections
the status flags
the Broadcast Group Delay
the GST to UTC parameters
TeleOrbit quickly authenticates with Goose
In late 2020 and the first half of 2021, TeleOrbit GmbH and Fraunhofer IIS worked on a project to implement the Galileo OSNMA capabilities onto its powerful and compact GNSS receiver lab “Goose”. This project, completed in May, successfully authenticated simulated OSNMA signals.
For the new phase, the team at Fraunhofer IIS adapted the setup to the newly published Interface Control Documents (ICDs) and receiver guidelines, and was able to authenticate the live signal on Nov. 16.
The screenshots below show snapshots of the Goose user interface with enabled OSNMA and successfully authenticated satellites, indicated by the green circle surrounding the blue Galileo satellites in the skyplot.
Interested users can sign up for this OSNMA test phase on GSC website. The site provides access to all corresponding documents and information, including the current ICD, receiver guidelines, OSNMA public key and Merkle Tree Root — both needed for the authentication process.
To learn about using GOOSE for your own tests and projects, contact [email protected].
integration with inertial measurement units (IMUs) and other sensors
positioning using cell phones and other consumer devices
any other areas or challenges they find particularly significant.
All four respondents in this issue, like to those in the January issue, report that they are making full use of the new GNSS signals available, taking hardware and software measures to counter jamming and spoofing, and integrating IMUs and other sensors with their GNSS receivers to help achieve continuous navigation and positioning in obstructed environments. In addition, they are continuing to develop mass-market applications, because high-precision positioning is becoming increasingly important for cellphones and wearable devices. For a fuller review of these trends, see my introduction to the first installment.
Notably, two of the companies featured in this issue, ComNav Technology and Unicore, are Chinese.
With Chad Pillsbury, Senior Director, Raytheon Intelligence & Space’s Resilient Navigation and Reconnaissance Solutions
Utilizing Galileo and BeiDou
Integration and fusion of multiple space position services is a key element in achieving assured positioning, navigation and timing (PNT). A combination of commercial and military-code navigation signals, when coupled with evolving sensors, provide more resilient methods of navigation and enable new concepts of operations related to PNT. Over the next two years, RI&S will customize these concepts of operation (CONOPS) for our United States and international allies to harness the power of fusion in resilience.
Dealing with jamming and spoofing
As threats to GPS continue to evolve and mature, RI&S continues to develop alternative navigation solutions, as well as GPS-capable receivers and antennas, aimed at defending against a variety of spoofing and jamming technologies. Our latest anti-jam, anti-spoof and high-precision solutions leverage a recent technology breakthrough that lowers size, weight, power and cost while boosting performance in the new M-code and alternative navigation applications.
Integration with IMUs and other sensors
IMUs are the cornerstone of high-performance navigation systems and will continue to be in the future. Recent innovations allow some systems to become more IMU agnostic, or even to consider microelectromechanical systems (MEMS) IMUs depending on performance, which can allow the customer greater flexibility and a more open architecture.
Positioning with consumer devices
RI&S sees 5G as a game-changing technology, with a lot of possibilities in the assured navigation market. We also look to cellphones as a great area of interest — especially for exploring unforeseen signals, considering human international models, and learning how the next generation of GPS users expect to see PNT information displayed.
Other significant challenges and opportunities
The future of GPS lies in a system-of-systems approach. Using time as a backbone, navigation systems can securely share time, data, position and intent across the network. Broadly, this approach can be used in civil, commercial and military environments. RI&S is fully focused on developing capabilities to achieve this ideal state.
Unicore Communications
With Gao Jingbo, Marketing Director
Utilizing Galileo and BeiDou
Most of Unicore’s high-precision products support all constellations and multiple frequencies. The new BeiDou 3 provides precise point positioning (PPP) service from three geostationary satellites via the B2b frequency, while Galileo offers up to five frequencies — E1, E5a, E5b, E5 AltBOC and E6. End users will benefit from improved PNT availability, reliability and continuity as access to those signals greatly reduces multipath effects and allows faster PPP convergence times.
Dealing with jamming and spoofing
To effectively deal with signal jamming and spoofing, it is important to know their sources. GNSS receivers also are susceptible to electronic interference and vulnerable to complex electromagnetic environments. Unicore integrates GNSS RF, baseband and algorithms into a single GNSS system-on-chip (SoC) that mitigates external interference. Joint time-frequency domain interference mitigation technology also is adopted in chip design.
Photo: Unicore Communications
Integration with IMUs and other sensors
Demand for seamless, accurate indoor-outdoor location is increasing. The integration of GNSS with IMUs, lidar, cameras and other sensors helps achieve continuous navigation and positioning in obstructed environments such as urban canyons and tunnels. Unicore offers receivers integrated with both high-end IMUs and affordable MEMS-based devices. Dual-frequency GNSS plus MEMS provides an ideal positioning solution for automotive applications.
Positioning with consumer devices
High-precision positioning is becoming increasingly important for cellphones and wearable devices, and multi-scenario adaptation is necessary. Instead of integrating standalone GNSS chips with smartphone processors, cellphone manufacturers prefer to cooperate with GNSS manufacturers through GNSS intellectual property (IP) licensing. To ensure high-precision service, better cellphone antennas are also important.
Other significant challenges and opportunities
We strive to deliver reliable, timely and smart positioning for anything, anywhere, anytime. Next-generation GNSS location products and services should be more end-user-friendly. The hardware interface will be more universal, flexible, configurable and adaptable with different algorithms for a diverse range of applications.
Teleorbit
With Daniel Seybold, CEO
Utilizing Galileo and BeiDou
Our GOOSE receiver has been able to use Galileo since its beginning and BeiDou since the forth quarter of 2020. Signals from both can be used individually or with other signals (GPS, Galileo, GLONASS and BeiDou, plus SBAS).
Dealing with jamming and spoofing
Open Service Navigation Message Authentication (OSNMA) is now implemented on the GOOSE, which helps mitigate spoofing attacks. GOOSE’s recording function enables users to record simulated jamming/spoofing attacks, and then analyze the behavior of the GOOSE and the received signals. We are developing various GNSS antenna arrays for nulling and beamforming, as well as a left- and right-hand circular polarized (LHCP/RHCP) antenna with GOOSE adaption for signal processing.
Signal conditioning on the GOOSE platform is based on a high-rate discrete Fourier transform (DFT)-based data manipulator algorithm, known as an HDDM algorithm, that fulfills multiple roles. The HDDM algorithm removes a wide range of interference signals, equalizes the spectrum, or restructures the spectrum.
Image: Teleorbit
Integration with IMUs and other sensors
We offer a GNSS antenna with an integrated IMU. Thanks to its open software interface, fusing IMU or other sensor data with GNSS data is easily done with GOOSE. Vector tracking, deep coupling and other sensor fusions (for example, 5G) are on the GOOSE roadmap.
Positioning with consumer devices
Our ongoing AMELIE project will study advanced techniques for the miniaturization and radiation enhancement of GNSS mass-market antennas to be applied in the design, manufacturing and testing of a multi-frequency, low-cost, high-gain dual circularly polarized antenna for the next generation of consumer devices. In 2021, we will build the following antenna demonstrators: single-frequency (L1/E1), dual-frequency (L1/G1/E1, L5/E5a/E5b) and multi-frequency (L1/G1/E1, L5/E5a/E5b, L2, E6).
Other significant challenges and opportunities
GOOSE can track the Galileo E5AltBOC (wideband) signal, which provides code-range variances below a few decimeters. This offers a significant increase in the accuracy of code measurements in terms of reduced noise and mitigation of multipath effects, compared to conventional signals. GOOSE will provide two different approaches for robust tracking: vector tracking for dealing with challenging environments where multipath occurs or buildings block signals, and adaptive tracking to allow the receiver to acclimate to its surroundings by adapting the bandwidth in the loop depending on movement, such as high dynamics.
ComNav Technology
With Min Xu, Director of GNSS Technology R&D Department
Utilizing Galileo and BeiDou
We keep up with the development of GNSS. Our new K8 series of high-precision GNSS modules support the recently completed BDS-3 and Galileo constellations concurrently, significantly improving positioning accuracy especially when signals are partially obstructed. Despite their complex design, the size of K8 modules decreased by almost 36% from their precursors and power consumption dropped to 1.0W, making them easier to integrate.
Dealing with jamming and spoofing
We have developed algorithms to eliminate specific forms of jamming and spoofing, with a focus on narrowband interference. The newly released Quantum III SoC chip — integrated with wideband signal-receiving technology, wideband and narrowband anti-interference technology, and anti-continuous wave interference technology — can provide high-quality observation information in a complex electromagnetic environment.
Photo: ComNav Technology
Integration with IMUs and other sensors
There is an increasing need to add IMUs to supplement obstructed GNSS signals. Empowered by a high-precision IMU, our N5 receiver supports tilt survey with accuracy of less than 2.5 cm. Users can survey without a centering bubble as its calibration-free tilt compensation protects it from magnetic disturbances. We are also focusing on image sensors, such as cameras and radars, to make data collection more flexible and reliable.
Positioning with consumer devices
Our high-precision products are mainly used in professional fields such as land surveying, deformation monitoring, and UAVs. We are continuing to explore GNSS products for consumer markets, which are sensitive to power consumption and cost. The upcoming M10 GNSS is a compact and portable receiver for mass-market applications, such as person or vehicle tracking and fleet management.
Other significant challenges and opportunities
GNSS technology can be widely applied in agriculture, transportation and infrastructure construction. We developed the AG360/AG360 Pro Agricultural Automatic Driving system, which drives autonomously without damaging crops. We collaborated with China Mobile to build more than 2,000 CORS stations to provide high-precision positioning services in support of smart-city construction, IoT and location-based services.
In the second part of our receiver feature, top receiver manufacturers discuss what’s on the horizon for GNSS receivers: recent and upcoming innovations, combating spoofing and jamming, fusing GNSS with other sensors, and the impact of increasing accuracy both for professional surveyors and consumers.
In January, we featured responses from NovAtel, Trimble, Unicore, Topcon, Hemisphere GNSS, CNC Navigation and Septentrio to questions about their recent and upcoming innovations in the design and manufacturing of GNSS receivers. We continue in this issue with responses to the same questions from Javad GNSS, Swift Navigation, Eos Positioning Systems, Tersus GNSS, TeleOrbit, Allystar Technology and NTLab.
All GNSS receiver manufacturers agree that spoofing and intentional and unintentional jamming are serious challenges. Their approaches to dealing with these challenges differ, however, as they rely on different combinations of technologies on both their receivers (such as monitoring cycle slips and using analog-to-digital converters, correlators and notch filters) and their antennas (such as using array antennas), as well as the new Galileo authentication service.
Photo: Tersus GNSS
Many receiver manufacturers now routinely use optical, inertial and other sensors — which continue to drop in price and increase in performance — to supplement GNSS signals where they are degraded or denied, especially in the automotive market.
Carrier phase positioning and correction services are increasingly improving the accuracy of survey stations and reducing their price. Meanwhile, submeter accuracy is spreading beyond surveying to other industries. Performance in challenging conditions also continues to improve, thanks largely to the increase in the number of GNSS constellations, available satellites and frequencies. (For a review of recent developments in antennas, see our companion article here.)
On the consumer side, the introduction of multi-frequency GNSS receiver chips, the increased use of correction services, and, in a few countries, the deployment of thousands of additional base stations will continue to increase the location accuracy of cell phones and other consumer devices, enabling new applications. However, in these devices size and cost limitations make antenna performance particularly challenging. (See Part 1 here.)
Javad GNSS
Jamming and Spoofing. “We protect you against jammers and spoofers like no one else can,” said Javad Ashjaee, founder and CEO of Javad GNSS. “We use multiple techniques to detect spoofers, the most important being the use of digital signal processing to detect more than one peak. First, with 864 channels and about 130,000 Quick Acquisition Channels in our Triumph chip, we have resources to assign more than one channel to each satellite to find all signals that are transmitted with that GNSS PRN code. If we detect more than one reasonable and consistent correlation peak for any PRN code, we know that we are being spoofed and can then identify the spoofer signals and ignore the wrong peak.”
An example of two peaks. (Chart: Javad GNSS)
Ashjaee described additional techniques:
The J-Shield filter blocks out-of-band interference.
Sixteen 255th-order FIR anti-jam digital filters protect against static in-band interference, and 16 adaptive 80th-order digital filters protect against dynamic interference.
Javad products measure the level of interference as a percentage of in-band noise above normal.
The Triumph chip has a powerful spectrum analyzer. Each spectrum shows the power and the shape of the interfering signals and jammers. This is more powerful and more efficient than using a commercial spectrum analyzer to evaluate the environment.
The chip also keeps a record of Automatic Gain Control, which is another indicator of external signals. A change in AGC can indicate interference.
Deviation of SNR from the expected value is another important indicator of interference.
“Usually there are over 100 signals available at any given time, and we need only four good signals to compute position. It is extremely unlikely that we can be spoofed without our knowledge.” Ashjaee concluded. “We will immediately recognize and take corrective actions.”
Jamming and spoofing protection is available on all Javad GNSS receivers and OEM boards. Read more about Javad GNSS’s jamming and spoofing protection in the December 2019 issue.
Sensor Fusion. “To support users in environments where GNSS RTK solutions are difficult or impossible to obtain,” Ashjaee said, “Javad GNSS has invented the J-Mate, which is a remotely controlled robotic EDM device and digital camera. GNSS RTK and optical can be seamlessly integrated using the J-Mate as the seventh RTK engine. Just set up a Triumph-3 on top of a J-Mate and a Triumph LS on top of a zebra rod, making the former pair the RTK base station and the latter pair the RTK rover.” Read more about Javad GNSS’s RTK and Optical United solution in the November 2019 issue.
Swift Navigation
Jamming and Spoofing. “Receivers have become more robust to intentional jamming by mimicking the jammers’ behavior to cancel it,” said Alex Pun, staff product manager for Swift. “Nevertheless, advanced jamming and spoofing mitigation often imply array antennas. A real evolution lies in considering these threats only in terms of the availability of the GNSS sensor, now part of a complete multi-sensor positioning engine such as Starling.”
Sensor Fusion. IMUs, visual sensors and GNSS will aid each other in different types of environments and scenarios, explained Pun. “Sensors are becoming more affordable, and their performance increases with each new generation. Sensor fusion will be the glue that will bind them to provide a precise positioning solution.”
Surveying. The combined use of carrier-phase positioning and correction services, such as Swift’s Skylark, will greatly improve accuracy and reduce the cost of survey stations, because they make their accuracy less dependent on the intrinsic performance of the receiver and the antenna, Pun said. “A global service eliminates the need for an individual base station.”
Consumer Devices. “The introduction of dual-frequency GNSS receivers from chip manufacturers will help improve positioning in cell phones and other consumer devices,” Pun said. “These chips, coupled with a widely available correction service such as Skylark, will greatly improve their performance accuracy to sub-meter levels.”
Other Challenges. Performance stability of the antenna and its characterization will become the main challenge to exploiting the new GNSS ASICs (application-specific integrated circuits) and correction services at their highest level of performance, Pun said. “A positioning engine can exploit this information to accelerate the convergence to the high-accuracy solution, and then improve its availability.”
Eos Positioning Systems
A surveyor uses the Arrow Gold receiver to map assets in Terrebonne, Quebec, Canada. (Photo: Eos Positioning)
“The past three years have seen considerable innovations and trends in the GNSS industry,” said Jean-Yves Lauture, CTO of Eos Positioning. “Receivers are becoming increasingly affordable and the adoption of higher-accuracy (submeter, centimeter) positioning by other industries, outside of conventional surveying, is growing. Considering the now four usable GNSS constellations and the aggressive launches of Galileo and BeiDou satellites, the number of available satellites and the list of frequencies they use has considerably increased.
“Although accuracy itself is not really improving, performance is — particularly in tougher conditions. It’s not uncommon for customers to use 30 to 35 satellites out of more than 40 in view using an Arrow Series GNSS receiver. The numbers are even higher in the Pacific regions, thanks to geostationary BeiDou satellites. This is, by far, more than double the number of satellites available with just GPS and GLONASS.”
Consumer Devices. “It will be challenging for smartphones and consumer devices to achieve survey-grade accuracy in the next few years. They face certain limitations. For instance, there is a cost and physical size associated with using a high-end GNSS antenna with a minimum of ground plane to achieve these levels of accuracy.
The Arrow Gold RTK GNSS receiver. (Photo: Eos Positioning)
“Also, it is unlikely that the manufacturers of consumer devices will invest in developing the advanced algorithms needed for a high level of constant accuracy and performance. In order to fit into a smartphone, consumer-grade GNSS chipset manufacturers must drop the use of many available signals and frequencies to keep both size and power consumption to a minimum.”
Allystar Technology
Photo: Allystar
Jamming and Spoofing. The GNSS chip in Allystar’s TAU1301 module supports eight adaptive notch filters to reduce the effects of GNSS jamming, explained Shi-Xian Yang, senior principal engineer in the company’s Baseband Algorithm Department. “It significantly improves the performance of GNSS tracking measurements, even in the presence of strong and fast-varying jamming signals.”
Sensor Fusion. The TAU1310 integrates a six-axis micro-electromechanical system (MEMS) gyro, which makes its affordable for the mass market, Yang said.
The Lenovo Z6. (Photo: Lenovo)
Consumer Devices. In its Z6 smartphone, Lenovo has taken advantage of the great improvement in multipath mitigation provided by the L5 signal’s higher chip rate and the output of high quality raw data via the TAU1302’s HD8040 GNSS chipset to improve the accuracy experience in the consumer market, Yang explained. Additionally, he pointed out, cell phones and other consumer devices now enable developers to access the raw sensor data from such sensors as accelerometers and barometers to input into their fusion algorithms.
Other Challenges. In the future, the TAU1310 could also support the L6 signal for PPP-RTK application.
NTLab
NTLab anti-jamming GNSS receiver. (Photo: NTLab)
Jamming and Spoofing. The problem of jamming and spoofing worries customers, according to Konstantin Yuriev, lead GNSS engineer at NTLab. The combination of anti-jam and anti-spoofing is in greater demand because the anti-jam feature alone is becoming insufficient. Yuriev cited the European Union’s new requirements for the European Railway Traffic Management System (ERTMS), which makes anti-spoofing mandatory.
The key issue today is “the solution to the problem of reducing the size and cost of anti-jam receivers, so that they become available to consumers on the civilian market. The key technology for this will be increasing the degree of integration of the component base, first creating a chipset for solving anti-jamming and anti-spoofing tasks, and then moving on to a single-chip solution. We have created a chipset and are ready to start work on the further integration into a single chip.”
Sensor Fusion. The traditional task of integrating data from a GPS antenna and a MEMS sensor has been solved, Yuriev said, with many such solutions on the market. One task is to track the antenna’s tilt. “The antenna, GNSS receiver, and MEMS sensors should be located very closely to each other — if possible, on a single small board,” Yuriev said. “Here, again, the solution is to increase the degree of integration, up to placing the baseband processor on the same chip with the digital CMOS circuitry of the MEMS sensor.” Another application of MEMS is serving as the core of an inertial navigation system (INS), providing an auxiliary subsystem for detecting the presence of spoofing. “This is more of an algorithmic task,” Yuriev said, “because traditional coupling using recursive filters is not enough. It is necessary to ensure the independence of the INS subsystem from the GNSS solution, or their intelligent mutual cross-control.”
Surveying. A major part of the cost of a survey-grade device, Yuriev pointed out, is for additional services, know-how, and other added values. There is market demand for a business model in which device price could go down while maintaining the main values for the customer. “This could be achieved if end-users tightly cooperate with hardware manufacturers, skipping third-party integrators. Alternatively, multiple third parties could compete, keeping the cost of the software low. One of the technical solutions for this is to provide software application programming interfaces (APIs) that will allow multiple third parties to offer application-level software for the same hardware. We call it the ‘open platform’ approach. One of our products implements this strategy.”
Other Challenges. Despite some skeptics, Yuriev argued, new GNSS systems have been successful. “A good example is IRNSS (NavIC), with India’s population of 1.3 billion forming a potential market. Moreover, according to our studies, good coverage is provided not only in India’s territory. We are working on creating an economically affordable solution with support for the NavIC S-band. A new chip-scale packaged RFIC (radio-frequency integrated circuit) should minimize the size, consumption, and price of NavIC-oriented modules, while maintaining all the advantages of the S-band signal in areas close to the equator. This is our solution to the problem.”
TeleOrbit
GOOSE platform. (Photo: Fraunhofer IIS)
GNSS Receiver Development Platform. The company’s GOOSE platform is a field-programmable gate array (FPGA)-based GNSS receiver, developed by Fraunhofer IIS, making it flexible in processing new or proprietary signals, according to Katrin Dietmayer, software development engineer at Fraunhofer IIS. “It comprises 60 hardware channels in real time and provides an open software interface for customer applications,” she explained.
Jamming and Spoofing. “It grants deep access to the hardware interface, down to, for example, the correlation values. Additionally, anti-jamming functions (such as notch-filter or pulse-blanker) can be added and anti-spoofing algorithms are already implemented. Thanks to the open architecture, our customers can also implement these or other algorithms.”
Sensor Fusion. Vector tracking in real time is already implemented on code base. Deep coupling with INS/IMU multi-sensor fusion — for example, with an odometer, ultra wideband or 5G — are possible and under development, Dietmayer said.
Surveying.TeleOrbit provides GNSS-RTK using RTKLIB. “The implemented Open GNSS Receiver Protocol (OGRP) is fully documented with a parsing tool using CONVBIN from RTKLIB as RINEX converter,” Dietmayer explained.
Consumer Devices. GOOSE is also used as the reference receiver in the ESA project Receiver Technologies for Future Mass Market (RT4FMM) devices. The project validates state-of-the-art dual-frequency mass-market receivers based on Broadcom BCM47755 and u-blox F9 and compares their performance against GOOSE E5AltBOC processing.
Other Challenges. GOOSE already processes the new Galileo OS-NMA (Open Service – Navigation Messages Authentication), while implementing the new Galileo High Accuracy Service (HAS) is on the roadmap. “The combination of these new features will result in a robust and reliable high-accuracy position,” Dietmayer said. “For system testing, the intermediate frequency signals can be recorded, processed and replayed with the platform.”
Tersus GNSS
The Oscar. (Photo: Tersus GNSS)
Jamming and Spoofing. Xiaohua Wen, founder and CEO, said his company has done much research and testing on jamming and spoofing. “We already implemented a high dynamic analog-to-digital converter to overcome jamming. To mitigate spoofing, we think that internet of things (IoT) devices can leverage cloud services. Alternatively, the new Galileo authentication service may serve the same function.”
Sensor Fusion.Tersus GNSS makes an INS product, and its Oscar receiver contains an inertial measurement unit (IMU). “The sensor fusion hub is a very hot topic in the automobile industry,” Wen said. “We are quickly adapting our Oscar and INS product line for the creation of high definition maps and for indoor navigation. We think it’s still the major pain point for a crowded country such as China.”
Surveying. As has been the case in many other industries, Wen said, the widespread adoption of GNSS technology and the increase in the number of players in the field has led to a drop in prices. “Tersus’ David and Oscar models are low cost but still perform well compared with Tier 1 players for professional survey machines using our own OEM GNSS board,” he said.
Consumer Devices. The fact that a few vendors are providing dual-frequency chipsets in smartphones opens the door for consumer-grade sub-decimeter applications, Wen said. “But we think the antenna could be a big challenge for the small devices.”
Other Challenges. “Mobile carriers are building thousands of base stations,” Wen said. “For example, Softbank in Japan completed 3,300 stations this year. China Mobile just issued a bid for a phase one project for 4,400 stations. We think mobile phone innovations for the new high-accuracy application may have some impacts in the coming years. We have been actively looking at some new GIS (geographic information systems) applications based on our in-house Nuwa platform.”
The GPS World Galileo Product Showcase, from the April 2015 issue, features the latest products from seven top companies.
GPS/GLONASS/Galileo Receiver
Septentrio AsteRx3 Photo: Septentrio
The AsteRx3 is a multi-frequency GPS/GLONASS/Galileo receiver is designed for demanding industrial applications. AsteRx3 features simultaneous high-quality GPS, GLONASS and Galileo tracking and a range of innovative features, such as the patented Galileo AltBOC tracking, the advanced multipath mitigation algorithm APME, LOCK+ tracking for exceptional tracking stability under high vibration conditions, RTK+ for extended RTK baselines and faster initialization, and AIM+, Septentrio’s Advanced Interference Mitigation technology, offering centimeter-level measurement quality for high-precision positioning, even in challenging environments.
The IFEN SX3 multi-GNSS software receiver Photo: IFEN
IFEN’s SX3 multi-GNSS software receiver tracks all known GNSS signals in view, including Galileo signals, in real time on a standard laptop now and in the foreseeable future (up to 1,000 channels in parallel on a core i7). The included RF front end offers four RF frequency paths with 50-MHz bandwidth each, covering the entire GNSS L-band spectrum. The USB 3.0 interface enables high-speed data transfer with up to 8-bit quantization. An optional dual RF input front end can be used for attitude determination, reflectometry and other applications requiring the synchronized input from two antennas. An optional built-in shock and vibration robust OCXO reference oscillator (MIL-STD 202G) is available, which replaces the standard high-quality TCXO normally used.
The SX3 software lets users configure the data processing, including changing loop bandwidths, integration times and the main processing rate, and choosing between different correlation types. The software includes a multi-correlator providing a two-dimensional (code and Doppler) correlation function visualization in real-time. The receiver comes with several powerful processing algorithms like vector tracking, to improve the tracking of weak signals in degraded environments.
The NEO-M8L Automotive Dead Reckoning (ADR) module by u-blox has integrated motion, direction and elevation sensors. The module integrates gyro and accelerometer with u blox’ GNSS platform M8 to achieve high indoor/outdoor positioning performance for road vehicle and high-accuracy navigation applications.
The module is able to track all visible GNSS satellites including GPS, GLONASS, BeiDou, QZSS and all SBAS, with Galileo to be supported in a future firmware version. Concurrent reception of two GNSS systems is supported. The NEO-M8L module can output a position up to 20 times per second.
In addition to accessing the integrated module’s gyro and accelerometer data, accident reconstruction systems can provide the location of an accident to facilitate insurance claims even if a collision occurs in a tunnel or park house. High-end navigation devices are able to guide drivers through tunnels of several kilometers because of the accuracy of u-blox’ ADR system. Stolen vehicles can be located instantly due to continuous monitoring of sensor data and storage of location in non-volatile memory.
The NovAtel FlexPak6D enclosed GNSS receiver is a flexible dual-antenna solution for application developers seeking a high-precision heading-capable positioning engine for space-constrained applications.
Designed for efficient and rapid integration, the compact receiver tracks Galileo as well as GPS, GLONASS and BeiDou. Antenna placement is flexible: the antenna baseline can be set according to space available on a vehicle and heading accuracy required. The modular OEM6 firmware enables users to configure the receiver for unique application needs. Scalable for sub-meter to centimeter-level positioning, the FlexPak6D delivers NovAtel’s ALIGN precision heading and relative heading firmware, as well as its GLIDE firmware for smooth decimeter-level pass-to-pass accuracy and RAIM for increased GNSS pseudorange integrity.
The GNSS simulator in the vector signal generator R&S SMBV100A Photo: R&S
The GNSS simulator in the vector signal generator R&S SMBV100A is designed for development, verification and production of GNSS chipsets, modules and receivers. The simulator supports all possible scenarios, from simple setups with individual, static satellites up to flexible scenarios generated in real time with up to 24 dynamic Galileo, GPS, GLONASS, BeiDou and QZSS satellites. The simulator also supports Assisted GNSS (A-GNSS) test scenarios, including generation of assistance data for Galileo.
The simulator offers real-time simulation of realistic constellations with up to 24 satellites and unlimited simulation time. Flexible scenario generation includes moving scenarios, dynamic power control and atmospheric modeling. Users can configure realistic user environments, including obscuration and multipath, antenna characteristics and vehicle attitude.
The all-in-one TRIUMPH-LS by JAVAD GNSS combines a high-performance 864-channel GNSS receiver, all-frequency GNSS antenna, and a modern featured handheld. The 864 all-in-view channels include Galileo E1/E5A/E5B, GPS L1/L2/L5, GLONASS L1/L2/L3, QZSS L1/L2/L5, BeiDou B1/B2 and SBAS L1/L5.
The TRIUMPH-LS offers GUIDE data collection, Visual Stake-out (VSO), navigation, six parallel RTK engines, more than 3,000 coordinate conversions, advanced CoGo features, and rich attribute tagging on a high-resolution, bright, 800 x 460 bright display. Two 3-megapixel cameras enable recording of images along with GNSS data.
With VSO, the virtual location of a point to be staked can be seen by a “flag” shown on the Triumph-VS camera image. This visual aid helps users navigate quickly to a point and makes stakeout jobs fast and easy. VSO can be used as a convenient way to get close to a target point before switching to the regular stakeout mode to perform precise measurements.
More than 100 channels are dedicated to continuous interference monitoring. The Triumph-LS monitors and reports interference graphically and numerically with patent-pending interference protection. Interference awareness allows safe GNSS operation in a city, airport and military environment.
The unit can serve as base or rover. It has a GSM modem, UHF transmit and receive, and an internal high-performance geodetic antenna.
The TRIUMPH-LS automatically updates all firmware when connected to a Wi-Fi Internet connection.
TeleOrbit’s software-defined radio receiver and GNSS interference monitoring tool receives and processes all available Galileo signals. Signals that are not yet transmitted and interference sources can be simulated and processed within the software tool.
Within a software-defined radio framework, the analog-to-digital converter is moved as close as possible to the antenna to perform most of the signal processing in software. This leads to adaptable solutions with lower hardware costs that can be easily extended to new signals and systems with only a software update.
The GNSS Software Defined Radio Receiver (GSDR2X) developed by TeleOrbit’s sister company TeleConsult Austria can track most readily available signals from Galileo, GPS and SBAS. By utilizing input from TeleOrbit’s GNSS multi-system performance simulation environment (GIPSIE), even signals not yet transmitted by satellites can be tracked and processed by the GSDR2X. Furthermore, input data can be read from various radio frequency front-ends, either directly or from file.
The modular GSDR2X framework enables new capabilities, such as the GNSS Interference Monitoring Tool (GIMT), which enables the GSDR2X to detect and classify interfering and jamming signals (see figure).
TeleOrbit’s software-based GNSS multi-system performance simulation environment, GIPSIE, consists of a satellite constellation simulator and an intermediate frequency simulator. The digital signal simulator GIPSIE streams the software-generated signals or recorded live data exactly into the receiver’s baseband processing chain to support development, test, verification, validation, qualification and certification.
Features include simulation of multi-system, multi-frequency scenarios GPS L1/L2/L5 and Galileo E1/E5/E6; simulation of jamming signals on top of the GNSS signals; simulation of Galileo PRS-like signals as well as the unencrypted GPS P-Code signals; record and replay of recorded and software generated data. GLONASS and BeiDou constellations and signals and simulation of micro-electro-mechanical sensors (MEMS) are coming soon.
Spirent Communications now offers SimSAFE, a software solution that simulates legitimate GNSS constellations along with spoofed or hoax signals to evaluate receiver resilience and help develop counter measures.
Hoax or spoofing attacks work by mimicking genuine GNSS signals, which mislead GNSS receivers. The military and critical infrastructure — such as wireless networks, banking, and utilities — are especially interested in being able to detect and reject spoofing attacks.
“GNSS signal vulnerability is becoming a significant issue,” said John Pottle, marketing director of Spirent’s Positioning Division. “The industry is beginning to talk more about vulnerability and how we actually think about categorizing the threat — what approaches are there to evaluate performance in the presence of interference signals? If you’re a developer, what approaches are there to clean up your performance? You’ll see us at Spirent being quite a bit more vocal about these areas in the coming months.”
SimSAFE was developed in conjunction with Qascom, a small organization of half a dozen GNSS signal security and authentication experts headed by Oscar Pozzobon, who served as the chief solutions architect for SimSAFE. Pozzobon contributed his knowledge of GNSS security and vulnerabilities, which were then integrated into the SimSAFE system.
SimSAFE provides a means of emulating a spoofing attack, and then monitoring a receiver under attack to evaluate mitigation strategies and countermeasures.
“SimSAFE really gets into details on how a receiver reacts in the presence of the hoax signals,” Pottle said. “By really understanding that, really getting into how is the receiver is acting and reacting, you can understand better how your receiver is likely to behave, and tune it up.”
The SimSAFE laboratory-based test solution is fully controllable, so that users can evaluate a receiver’s response to a wide range of spoofing attacks. As Pottle put it, when fed both authentic and spoofed signals, “What’s the receiver going to see? It’s going to see the authentic signals, it’s going to see a couple of spoofed signals. And you can play around with the spoofed signals — that’s the controllable bit. While this is happening, the detector module within SimSAFE monitors and reports the receiver’s response to the attacks. At its most simple, that’s the power of SimSAFE.”
SimSAFE is aimed not only at receiver developers, a core audience of Spirent’s, but at anyone trying to build a system that may be subject to intentional interference, such as in the military or critical infrastructure. “Those people are starting to ask questions about what should I be worried about? What kind of an attack might I be open to? How can I be sure, if I’ve got a choice of three or four receivers, that I’m going to choose one that meets my needs in terms of resilience to intentional interference?” Pottle said. “Our belief is that SimSAFE will allow people to evaluate different receivers and strategies for mitigating spoofing attacks, and therefore help them to build the right level of resilience in their systems.”
SimSAFE is available in two variants. SimSAFE Simulated uses the simulator for all signals, both satellite and spoofed, using one or more channels for the spoofed signal.
Instead of a simulator, SimSAFE Live pulls authentic signals from sky with an antenna, so the user has the full power of the simulator to generate a much broader range of spoofing attacks. “The clever bit is aligning the spoofed signal with the real signal, getting the timing and frequency synced up,” Pottle said.
Spirent is also working on other technologies to mitigate spoofing, including work with interference signals from ground-based transmitters, adaptive antenna lab-based tests, and integration with inertial sensors, such as in military jets.
