Solutions and Innovation
Advances in technology have become such an integral part of day-to-day life that we can hardly imagine a world without them. We are truly living in the day of the Jetson’s.
It would be unbearable to imagine a failure or loss of access to any of our technologies such as the Internet, and smart phones. However, there is a technology which is just as omnipresent as the Internet that most of us do not even realize we use constantly … GPS.
Over fifty years ago, who knew how pervasive GPS would become? When we think of GPS, most of us think of our smart phone or car navigation system. However, GPS is the world standard for Positioning, Navigation, and Timing (PNT). From natural interferences to growing terrorist threats, our total dependence on GPS is problematic. There is hardly a system today (military or commercial) that is not totally dependent on GPS for position and/or time. Without it, financial systems may fail, autonomous vehicles might crash, military missions could fail, and lives could be lost.
Our solution is critical to meeting US National Defense needs
Section 1618 of the 2017 National Defense Authorization Act (NDAA), “Backup and Complementary Positioning, Navigation and Timing Capabilities of Global Positioning System (GPS)”.
To meet ever-growing threats of both, natural and man-made environments, and evolving adversary countermeasures, there is a need to PNT solutions that are not completely reliant on GPS.
Accurate and reliable positioning and timing is critical to a variety of applications.
Last year, during GPS satellite maintenance, an incorrect time was accidentally uploaded to several GPS satellites, making them “out of sync” by the fractions of fractions of seconds.
The minute error disrupted GPS-dependent timing equipment around the world for more than 12 hours. In parts of the U.S and Canada, police, fire, and EMS radio equipment stopped functioning. BBC digital radio was out for two days in many areas, and the anomaly was even detected in electrical power grids.
As another example, in 2018, a joint forces unit was on a mission against a high-value target when they were ambushed and pinned down. When interviewed, the Joint Terminal Attack Controller (JTAC) said, “Because of the tree cover, the aircraft overhead couldn’t see me or the target. I had to continually leave the protection of cover in order adjust the rounds.” Eventually the airstrikes were called in, allowing the unit to withdraw.
These are just a couple examples of where our solution for a more reliable Positioning, Navigation, and Timing (PNT) system (NavXTM) is highly beneficial and leads to increased mission success and save lives!!
We currently offer two primary products:
- NavXTM – low SWaP-C (Size, Weight, Power, Cost) device that provides reliability, accuracy, and robustness for PNT in TOTAL GPS denial
- escULP-TCTM – chip size Ultra-Low Power (ULP) Timing Circuit that bridges the gap between low-cost commercial oscillators (XO) and very high cost and power Chip Scale Atomic Clocks (CSAC).
NavXTM
NavXTM is based on a commercially available GPS product with layers of capabilities added to provide resiliency and accuracy when GPS signals are unavailable or unreliable. Many competitive products tend to focus on one technology. This limits their ability to address application across a wide variety of applications.
We offer NavXTM as a standalone device, or as an embedded board. Some of the technology layers may also be licensed as software components.
The airways are full of Radio Frequency (RF) signals that were not necessarily intended for positioning. Our solution has been designed and developed to be flexible/configurable to leverage many of these RF “Signals of Opportunity” (SOOP) as positioning information.
In September 2020 we successfully delivered a proof-of-concept operational prototype to US Air Force Lifecycle Management Center (AFLCMC). This prototype added the use of signals from non-positioning Low Earth Orbit (LEO) satellite as a source of positioning. We were able to calculate position data based on LEO satellite signals only and visualize the position on military systems (Android Team Awareness Kit – ATAK). Our customer declared our proof-of-concept “very successful.” (final customer evaluation report expected March 2021)
A 100 sec video may be viewed at:
https://youtu.be/RNqhAtszjsI
Being at a much lower orbit than GPS satellites, LEO satellite signals are much stronger and reliable. There are currently hundreds of LEO satellites broadcasting over a much wider spectrum of frequencies which makes them far more difficult to spoof or jam. In the next few years, it is anticipated that mega-constellations such as Space-X’s Starlink will be launched, making thousands of new satellites available for positioning information.
By adding the use of other signal sources, like LEO satellite signals, we can literally assure signal availability and PNT in GPS denied environments. Unlike other competitive products, our solution does NOT rely on signal content and is NOT reliant on costly receivers/services (i.e. GlobalStar, Iridium).
This same architecture is being leveraged for a number of new business opportunities including: 1) to pursue a current Navy SBIR for use of Very Low Frequency (VLF) RF signals for PNT on Navy vessels (surface and submerged); 2) Naval Research Labs (NRL) sole-source award for configurable SOOP PNT.[/modal_popup_box]
The foundation of escPNTTM is a commercially available product that provides a low SWaP-C solution for accurate position/time in GPS challenged environments. Low SWaP-C enable us to meet growing market demand in markets that are currently very underserved including small UAS, personal (tactical-level airmen), small ground autonomous vehicles, precision weapons, and many more. Our solution is also applicable to other markets that currently utilize much larger, heavier, greater power consumption and expensive devices such as larger manned aircraft and maritime application (commercial and military). At the core of escPNTTM is our tightly coupled sensor fusion algorithm that fuses a wide variety of information to produce an accurate and reliable position. This includes 3 Global Navigation Satellite System (GNSS) receivers, Inertial Measurement Unit, crystal clock, barometer, and temperature sensor. Multiple standard interfaces enable access to other sensors and sources of information.
By utilizing multiple sources of information, we provide a resilient centimeter accurate PNT in GPS/GNSS “challenged” environments (where GPS and other GNSS satellite signals may be unreliable due to weather conditions, RF signal noise, signal reflections off buildings, obstructed by trees/buildings, etc.) for some short time (1-5 minutes).
Real-time kinematic (RTK) corrections are applied to enable positional accuracy to 2 centimeters!![/modal_popup_box]
The small size makes NavXTM applicable to large and growing markets, such as small Unmanned Aircraft Systems (UAS).
Our escULP-TCTM product is a component of NavXTM and enables our solution to provide continuous/accurate PNT when other solutions would fail over time.
escULP-TCTM
It is sometimes forgotten that the “T” in PNT stands for “TIME” and many systems rely on GPS for accurate time. Current PNT solutions leverage internal clocks/oscillators to maintain time when GPS signals are unavailable. However, the lower SWaP-C clocks/oscillators tend to “drift” over short periods of time (minutes). This is acceptable when GPS is “challenged”/spotty due to obstructions (urban canyons, tree cover, etc.) but is totally unacceptable when GPS is denied for hours or days. One solution to this problem is use of Chip Scale Atomic Clocks (CSAC). The problem is current technology CSACs are high power consumers. For mobile applications (i.e. small UAS, precision weapons, handheld radios, etc.), this drives the need for additional power/batteries.
esc Aerospace has partnered with researchers at Northeastern University to create an affordable Ultra-Low Power (ULP) Timing Circuit (escULP-TCTM) that bridges the gap between low SWaP-C commercial oscillators (XO) and very high SWaP-C CSACs. Our new escULP-TCTM will enable significant positional accuracy improvements of our NavXTM and enable utilization in total GPS denial without positional/time “drift.” The market potential for escULP-TCTM by itself is significant, especially in the emerging field of the Internet-of-Things (IoT).
