Emcore achieved success in an ultra-high-altitude flight simulation conducted by CAST Navigation, which tested Emcore’s SDN500 inertial navigation system (INS).
Emcore is a provider of advanced mixed-signal products that serve the aerospace & defense and broadband communications markets.CAST Navigation builds simulators for testing and validating GNSS/INS performance in high-end navigation systems.
CAST used Emcore’s SDN500 inertial navigation system (INS) for the test, which required simulating performance at an altitude more than 24,000 meters and velocities over 600 m/s. Only a few aircraft in the world have such capabilities, including the SR-71 Blackbird, but it is not practical to participate in a test flight on the SR-71. Simulating the SDN500 INS test flight to specific customer profiles on a CAST system is straightforward and cost-effective.
Testing began with a stationary period on the ground while the SDN500 initialized and transitioned into air-navigation mode. Then the flight trajectory entered a series of maneuvers, speed and altitude changes that provided observability for various parameters with corresponding changes in the calculated figures.
Emcore relies on GNSS/INS simulators for hardware-in-the-loop testing to verify the expected performance of algorithms. Emcore CORE sought to validate the velocity and altitude limits of a new GNSS receiver along with the algorithm performance in a tactical-grade SDN500 system. In the final analysis, the GNSS receiver and navigation algorithm was confirmed to operate as expected throughout the operation for all three of the customer’s dynamic constraint scenarios.
“We were extremely pleased to demonstrate how Emcore takes advantage of the functionality contained in the CAST simulator to prove-out our robust product performance in customer environments,” said David Hoyh, director of sales and marketing for navigation products, Emcore..
“During the times when there was no valid solution from the GNSS receiver, the algorithm maintained an accurate solution using only the data from the IMU,” explained Andy Williams, senior field application engineer at Emcore who spearheaded the effort. “In addition, there was no algorithm instability or discontinuity when the GNSS receiver resumed, providing a solution to the algorithm. Throughout this entire profile, even when GNSS signal is lost, the SDN500 maintains an accurate navigation solution. This test is not possible without the synchronized GNSS radio frequency and trajectory matching IMU data provided by the CAST system.”
Source: “A True Reference. Theory Meets Reality in Synchronized Simulation Environments,” Inside GNSS, Volume 15/Number 5, September/October 2020, Pages 28, 29, 30.
In a special advertiser-sponsored section of our October issue, we spoke with prominent GNSS companies about their current solutions for today’s industry challenges.
Q&A with CAST Navigation
Answered by Lou Pelosi, vice president
Lou Pelosi, vice president
Q: What is your most proven GNSS solution?
A: CAST Navigation does not supply GNSS receivers (GNSS solutions), rather we manufacturer GNSS simulators which are used to test GNSS receivers. CAST has had the most success with our GNSS/INS simulator. It provides an Embedded GPS Inertial (EGI) navigator with coincident GPS and inertial data. The EGI “thinks” it is moving while it remains stationary.
With our GNSS/INS simulator, the operational flight program of the EGI can be tested. During development of a platform’s navigation system, the CAST simulator is used to recreate the identical test conditions as the EGI’s software is modified. Once the platform’s navigation system is finalized, the output of the EGI is used to drive other systems, such as flight control or radar.
The GNSS/INS simulator can also include Controlled Radiation Pattern Antenna (CRPA) test features. If the EGI being used by the platform has an anti-jam antenna, the simulator can also test that feature.
The CAST GNSS/INS simulator has proven to be a key piece of equipment in system integration laboratories as new aircraft are developed.
Photo: CAST Navigation
Q: What are the solution’s key specs?
A: A key element of our GNSS/INS simulator is the inertial model contained in the simulator. It is a whole value inertial model rather than an error model. In its normal state, it reacts in the same manner as the actual inertial of the EGI. It also had degraded modes that are used to simulate hardware failures. When analyzed by the EGI manufacturers, its noise characteristics are almost identical to fielded navigation systems.
Q: What are the solution’s key features and benefits?
A: The most obvious benefit of using a CAST GNSS/INS simulator is cost savings. Even with the cost of lab equipment and personnel, there is still a savings over flight testing. A key feature of using a simulator for testing is its repeatability. Every time you rerun a test; the conditions are the same. In the real world, the satellites change constantly. Being able to accept real-time trajectory data is another key feature of CAST simulators. Instead of using our internal point mass model for scenario generation, an actual flight profile can be sent to the simulator from an external computer.
CAST has also been authorized by the GPS Directorate to provide classified functions to authorized users. Available options include Y-code, SAASM and M-code MNSA.
A: Kolmostar specializes in ultra-low-power, instant cold-boot GNSS positioning solutions for internet of things (IoT) applications, mobile devices and beyond.
Q: What are the solution’s key specs?
A: Our advanced GNSS positioning module JEDI-200 is specially designed for location-based IoT applications such as asset tracking, fleet management, pet/livestock tracking, smart wearables and share economy. It is also optimized for integration with LPWAN (low power wide area network) technologies such as LoRaWAN®/NB-IoT/LTE-M to provide the ultimate ultra-low-power profile for IoT applications. There are two outstanding advantages of JEDI-200: ultra-low-power and instant cold-boot. With 25 mW power consumption and the revolutionary 1-second TTFF (time to first fix), JEDI-200 is able to reduce the energy consumption to get one position fix by up to 120x compared to traditional GNSS modules on the market.
Q: What are the solution’s key features and benefits?
Photo: Kolmostar
A: GNSS/GPS sensors are one of the most power-consuming sensors in IoT or mobile devices. Battery life will be significantly shortened when GNSS/GPS sensors are turned on. Hence, many IoT and mobile devices either do not include GNSS/GPS sensors or have to equip themselves with very large batteries, incurring much inconvenience and cost. Kolmostar’s ultra-low-power and instant cold-boot JEDI-200 module is specially designed to solve this long-standing industry pain point.
With its ultra-low-power feature, JEDI-200 is able to reduce the energy consumption to get one position fix by up to 120x when compared to traditional GNSS modules. IoT devices with very limited-sized batteries are now able to have GNSS positioning ability while still maintaining a battery life up to 10+ years. Another key feature of JEDI-200 is instant cold boot. Unlike traditional GNSS modules’ 30-second TTFF in cold boot, JEDI-200 can achieve an instant 1-second TTFF, providing a better and more seamless customer experience when short latency/response time is particularly desired in certain applications. In addition, JEDI-200 is optimized for LPWAN technologies such as LoRaWAN®/NB-IoT/LTE-M, further reducing both the cost and the power consumption of devices’ wireless communication, which is another big challenge most IoT and mobile devices previously faced.
A: The LabSat 3 Wideband GNSS simulator offers multi-constellation and multi-frequency capabilities for reliable, repeatable and consistent testing. Its one-touch Record and Replay provides an efficient way to test and develop GNSS receivers without the cost, inconvenience and limitations of live-sky signals. Combining LabSat with the custom simulation software SatGen enables the creation of GNSS RF I&Q or IF data files based on a bespoke scenario, allowing for almost any kind of test at a set time, date and location.
Q: What are the solution’s key specs?
A: With three channels, a bandwidth of up to 56 MHz and 6-bit sampling (3-bit I and 3-bit Q), LabSat 3 Wideband can handle almost any combination of constellations and signals that exists today, with plenty of spare capacity for future planned signals.
Q: What are the solution’s key features and benefits?
A: LabSat 3 Wideband is small and affordable, making it an ideal solution for companies to provide their employees with a suitable method of testing their GNSS devices whilst working from home. In addition to its compact size, an internal battery delivers up to two hours of run time to record scenarios in even the most challenging field environments.
Photo: Labsat
It is incredibly user friendly with one touch record and replay and an HTML interface that makes setup simple and problem-free. A range of additional signals can also be recorded and synchronized to the GNSS input: dual-CAN, RS232 and digital inputs are simultaneously captured, increasing the level of playback realism and allowing for a wider range of testing.
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, and takes advantage of the LabSat 3 Wideband’s ability to read RF data at up to 95 MB/s. Creating an artificial scenario using SatGen allows for precise control of the data content, creating a standardized file for repeatable testing and carrying out true comparisons between receivers.
The versatility of the LabSat 3 Wideband makes it a familiar sight on the desks and benches of technology companies around the world. From GNSS device and application testing to receiver sensitivity and end-of-production-line testing, LabSat 3 Wideband is a perfect testing partner.
Q: What is Trimble OEM GNSS’ most proven GNSS solution?
A: The Trimble BX992 is the flagship product from the Trimble OEM GNSS portfolio, proven in multiple environments and applications. Powered by the BD992-INS receiver module, this rugged yet compact enclosure allows original equipment manufacturers and system integrators to rapidly integrate precise position and orientation data to guidance, control and autonomous applications. Continuous data sets collected from test sites and real-world applications around the world have been used to create a powerful engine that performs in the most challenging of GNSS environments.
The Trimble BX992. (Photo: Trimble)
Q: What are the solution’s key specs?
A: The Trimble BX992 delivers low-latency 100-Hz centimeter-level positions with tight integration of IMU sensor data and GNSS observations in the RTK/RTX engine. The rugged IP67 enclosure supports multi-frequency tracking from GPS, Galileo, GLONASS, BeiDou, QZSS and NavIC constellations. The dual-antenna inputs allow rapid and robust alignment of onboard gyro sensors. With Trimble RTX correction services, the BX992 delivers reliable, high-accuracy positioning without a local base station or cell modem.
Q: What are the solution’s key features and benefits?
A: The BX992 is a full-featured solution with an onboard spectrum analyzer, a critical tool for developers to identify interference from unwanted signals, thus allowing products to be released to the market within specification and on schedule.
CAST Navigation LLC has developed the capability to support development and implementation of the Modernized Navstar Security Algorithm (MNSA). The U.S. Department of Defense granted in January CAST MNSA security approval, enabling its simulators to test M-code.
The new software will support M-code using the classified security algorithm. M-code is an updated GPS military signal that is part of the modernization of the current GPS constellation.
The CAST-MNSA is a significant addition to CAST Navigation’s suite of classified signal capabilities and is available on all of the company’s simulators. The feature will be instrumental in the effort toincorporate MNSA capability into GPS receivers. CAST provides development, integration and testing life-cycle support for the next generation of navigation systems.
“Our GNSS/INS simulators and test equipment are critical tools used to validate and verify the performance of navigation systems, and this feature ensures that our customers can keep pace with advances in technology and capability,” said Susan Gove, president and CEO of CAST Navigation.
“The classified product feature continues our 38-year history of innovation as anindustry leader whose products are critical to the support of numerous government, military, prime contractors and U.S. Department of Defense programs,” Gove said.
