Difference between revisions of "Time"

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<b>Satellite Navigation Systems Overview with John Pottle
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<b>How did Planes Fly Before GPS?
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</b><br>Royal Institute of Navigation  John Pottle, Director of the Royal Institute of Navigation, will put into context what the hundreds of navigation satellites in space are all for and how they work together.  This webinar will explain the similarities and differences between global and regional satellite navigation systems, how they are co-ordinated, and by whom.  The space-based augmentation systems will also be covered: what are these and how do they help?  *During the webinar Q&A there was a question about whether or not GNSS could be used for moon missions - please see: Website: http://rin.org.uk/   
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</b><br>How did Planes Fly Before GPS?:
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The Wright Brothers first took to the skies in 1903 but GPS wasn't publicly available until 1983, so how did planes traverse the world in those 80 years? From celestial navigation to dead reckoning, to the firsts forms of radio telemetry (like adock range stations and LORAN) we'll be discussing them all in this video. Discord: http://discord.gg/DUvyS8n Amazon Affiliate Link*: http://amzn.to/3kNTHhK  
 
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GPS receivers that use the L5 band can pinpoint to within 30 centimeters or 11.8 inches. The GPS concept is based on [[time]] and the known position of GPS specialized satellites. The satellites carry very stable atomic clocks that are synchronized with one another and with the ground clocks. Any drift from time maintained on the ground is corrected daily. In the same manner, the satellite locations are known with great precision. GPS receivers have clocks as well, but they are less stable and less precise.  Each GPS satellite continuously transmits a radio signal containing the current time and data about its position. Since the speed of radio waves is constant and independent of the satellite speed, the time delay between when the satellite transmits a signal and the receiver receives it is proportional to the distance from the satellite to the receiver. A GPS receiver monitors multiple satellites and solves equations to determine the precise position of the receiver and its deviation from true time. At a minimum, four satellites must be in view of the receiver for it to compute four unknown quantities (three position coordinates and clock deviation from satellite time).  [http://en.wikipedia.org/wiki/Global_Positioning_System Global Positioning System | Wikipedia]
 
GPS receivers that use the L5 band can pinpoint to within 30 centimeters or 11.8 inches. The GPS concept is based on [[time]] and the known position of GPS specialized satellites. The satellites carry very stable atomic clocks that are synchronized with one another and with the ground clocks. Any drift from time maintained on the ground is corrected daily. In the same manner, the satellite locations are known with great precision. GPS receivers have clocks as well, but they are less stable and less precise.  Each GPS satellite continuously transmits a radio signal containing the current time and data about its position. Since the speed of radio waves is constant and independent of the satellite speed, the time delay between when the satellite transmits a signal and the receiver receives it is proportional to the distance from the satellite to the receiver. A GPS receiver monitors multiple satellites and solves equations to determine the precise position of the receiver and its deviation from true time. At a minimum, four satellites must be in view of the receiver for it to compute four unknown quantities (three position coordinates and clock deviation from satellite time).  [http://en.wikipedia.org/wiki/Global_Positioning_System Global Positioning System | Wikipedia]
  
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<b>Satellite Navigation Systems Overview with John Pottle
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</b><br>Royal Institute of Navigation  John Pottle, Director of the Royal Institute of Navigation, will put into context what the hundreds of navigation satellites in space are all for and how they work together.  This webinar will explain the similarities and differences between global and regional satellite navigation systems, how they are co-ordinated, and by whom.  The space-based augmentation systems will also be covered: what are these and how do they help?  *During the webinar Q&A there was a question about whether or not GNSS could be used for moon missions - please see: Website: http://rin.org.uk/ 
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<b>How to fool a GPS - Todd Humphreys
 
<b>How to fool a GPS - Todd Humphreys
 
</b><br>TED-Ed  Todd Humphreys forecasts the near-future of geolocation when millimeter-accurate GPS "dots" will enable you to find pin-point locations, index-search your physical possessions ... or to track people without their knowledge. And the response to the sinister side of this technology may have unintended consequences of its own. (Filmed at TEDxAustin.)  Talk by Todd Humphreys.
 
</b><br>TED-Ed  Todd Humphreys forecasts the near-future of geolocation when millimeter-accurate GPS "dots" will enable you to find pin-point locations, index-search your physical possessions ... or to track people without their knowledge. And the response to the sinister side of this technology may have unintended consequences of its own. (Filmed at TEDxAustin.)  Talk by Todd Humphreys.
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<b>PULP-DroNet -- Autonomous Artificial Intelligence-powered Nano-Drone
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</b><br>PULP-DroNet is a deep learning-powered visual navigation engine that enables autonomous navigation of a pocket-size quadrotor in a previously unseen environment.
 +
Thanks to PULP-DroNet the nano-drone can explore the environment, avoiding collisions also with dynamic obstacles, in complete autonomy -- no human operator, no ad-hoc external signals, and no remote laptop! This means that all the complex computations are done directly aboard the vehicle and very fast.  The visual navigation engine is composed of both a software and a hardware part. The former is based on the previous DroNet [1] project developed by the RPG [2] from the University of Zürich (UZH).  DroNet is a shallow convolutional neural network (CNN) which has been used to control a standard-size quadrotor in a set of environments via remote computation. The hardware soul of PULP-DroNet is embodied by the PULP-Shield an ultra-low power visual navigation module featuring a Parallel Ultra-Low-Power (PULP) GAP8 System-on-Chip (SoC) from GreenWaves Technologies [3], an ultra-low power camera, and off-chip Flash/DRAM memory; the shield is designed as a pluggable PCB for the Crazyflie 2.0 [4] nano-drone. Then, we developed a general methodology for deploying state-of-the-art deep learning algorithms on top of ultra-low power embedded computation nodes, like a miniaturized drone. Our novel methodology allowed us first to deploy DroNet on the PULP-Shield, and then demonstrating how it enables the execution the CNN on board the CrazyFlie 2.0 within only 64-284mW and with a throughput of 6-18 frame-per-second! Finally, we field-prove our methodology presenting a closed-loop fully working demonstration of vision-driven autonomous navigation relying only on onboard resources, and within an ultra-low power budget. We release here, as open source, all our code, hardware designs, datasets, and trained networks.  Reference: D. Palossi, F. Conti, and L. Benini An Open Source and Open Hardware Deep Learning-powered Visual Navigation Engine for Autonomous Nano-UAVs Preprint: https://arxiv.org/abs/1905.04166  PULP-Platform Project Webpage: https://www.pulp-platform.org/
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<b>The Coming Revolution in MEMS Gyroscopes and MEMS Inertial Sensors
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</b><br>Wireless Integrated MicroSensing & Systems - WIMS2  Relevant for automotive robotic drone wearable applications.
 
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Revision as of 08:41, 17 November 2020

YouTube search... ...Google search


Whenever we have developed better clocks, we’ve learned something new about the world.
- Alexander Smith New Time Dilation Phenomenon Revealed: Timekeeping Theory Combines Quantum Clocks and Einstein’s Relativity - Dartmouth College


The Earth's rotation is so accurate it varies only in milliseconds ...do you feel the Earth rotation slowing down?


DARPA Making Progress on Miniaturized Atomic Clocks for Future PNT Applications | US Defense Advanced Research Projects Agency (DARPA)


Navigation Aids

YouTube search... ...Google search

Navigation is a field of study that focuses on the process of monitoring and controlling the movement of a craft or vehicle from one place to another.[1] The field of navigation includes four general categories: land navigation, marine navigation, aeronautic navigation, and space navigation. Navigation | Wikipedia

Navigation Systems
ERAU SpecialVFR

How did Planes Fly Before GPS?
How did Planes Fly Before GPS?: The Wright Brothers first took to the skies in 1903 but GPS wasn't publicly available until 1983, so how did planes traverse the world in those 80 years? From celestial navigation to dead reckoning, to the firsts forms of radio telemetry (like adock range stations and LORAN) we'll be discussing them all in this video. Discord: http://discord.gg/DUvyS8n Amazon Affiliate Link*: http://amzn.to/3kNTHhK

GPS: The Global Positioning System

YouTube search... ...Google search


GPS receivers that use the L5 band can pinpoint to within 30 centimeters or 11.8 inches. The GPS concept is based on time and the known position of GPS specialized satellites. The satellites carry very stable atomic clocks that are synchronized with one another and with the ground clocks. Any drift from time maintained on the ground is corrected daily. In the same manner, the satellite locations are known with great precision. GPS receivers have clocks as well, but they are less stable and less precise. Each GPS satellite continuously transmits a radio signal containing the current time and data about its position. Since the speed of radio waves is constant and independent of the satellite speed, the time delay between when the satellite transmits a signal and the receiver receives it is proportional to the distance from the satellite to the receiver. A GPS receiver monitors multiple satellites and solves equations to determine the precise position of the receiver and its deviation from true time. At a minimum, four satellites must be in view of the receiver for it to compute four unknown quantities (three position coordinates and clock deviation from satellite time). Global Positioning System | Wikipedia

s
b

Satellite Navigation Systems Overview with John Pottle
Royal Institute of Navigation John Pottle, Director of the Royal Institute of Navigation, will put into context what the hundreds of navigation satellites in space are all for and how they work together. This webinar will explain the similarities and differences between global and regional satellite navigation systems, how they are co-ordinated, and by whom. The space-based augmentation systems will also be covered: what are these and how do they help? *During the webinar Q&A there was a question about whether or not GNSS could be used for moon missions - please see: Website: http://rin.org.uk/






HH1
BB1

HH2
BB2

HH3
BB3

HH4
BB4

HH5
BB5

HH6
BB6

HH7
BB7

What On Earth Is Cubesat?
BB8



Assured-Positioning, Navigation and Timing (A-PNT)

YouTube search... ...Google search

Like the GPS units in many automobiles today, a simple receiver and some processing power is all that is needed for accurate navigation. But, what if the GPS satellites suddenly became unavailable due to malfunction, enemy action or simple interference, such as driving into a tunnel? Unavailability of GPS would be inconvenient for drivers on the road, but could be disastrous for military missions. Extreme Miniaturization: Seven Devices, One Chip to Navigate without GPS | US Defense Advanced Research Projects Agency (DARPA)

Securing Positioning & Timing 2: GPS/GNSS Vulnerability Types and Examples
Royal Institute of Navigation The second of a series of webinars from the Securing Positioning & Timing short course. This webinar covers GPS/GNSS Vulnerability Types and Examples. Presented by Guy Buesnel. Supported by the UK Space Agency. Website: http://rin.org.uk/

How to fool a GPS - Todd Humphreys
TED-Ed Todd Humphreys forecasts the near-future of geolocation when millimeter-accurate GPS "dots" will enable you to find pin-point locations, index-search your physical possessions ... or to track people without their knowledge. And the response to the sinister side of this technology may have unintended consequences of its own. (Filmed at TEDxAustin.) Talk by Todd Humphreys.

PULP-DroNet -- Autonomous Artificial Intelligence-powered Nano-Drone
PULP-DroNet is a deep learning-powered visual navigation engine that enables autonomous navigation of a pocket-size quadrotor in a previously unseen environment. Thanks to PULP-DroNet the nano-drone can explore the environment, avoiding collisions also with dynamic obstacles, in complete autonomy -- no human operator, no ad-hoc external signals, and no remote laptop! This means that all the complex computations are done directly aboard the vehicle and very fast. The visual navigation engine is composed of both a software and a hardware part. The former is based on the previous DroNet [1] project developed by the RPG [2] from the University of Zürich (UZH). DroNet is a shallow convolutional neural network (CNN) which has been used to control a standard-size quadrotor in a set of environments via remote computation. The hardware soul of PULP-DroNet is embodied by the PULP-Shield an ultra-low power visual navigation module featuring a Parallel Ultra-Low-Power (PULP) GAP8 System-on-Chip (SoC) from GreenWaves Technologies [3], an ultra-low power camera, and off-chip Flash/DRAM memory; the shield is designed as a pluggable PCB for the Crazyflie 2.0 [4] nano-drone. Then, we developed a general methodology for deploying state-of-the-art deep learning algorithms on top of ultra-low power embedded computation nodes, like a miniaturized drone. Our novel methodology allowed us first to deploy DroNet on the PULP-Shield, and then demonstrating how it enables the execution the CNN on board the CrazyFlie 2.0 within only 64-284mW and with a throughput of 6-18 frame-per-second! Finally, we field-prove our methodology presenting a closed-loop fully working demonstration of vision-driven autonomous navigation relying only on onboard resources, and within an ultra-low power budget. We release here, as open source, all our code, hardware designs, datasets, and trained networks. Reference: D. Palossi, F. Conti, and L. Benini An Open Source and Open Hardware Deep Learning-powered Visual Navigation Engine for Autonomous Nano-UAVs Preprint: https://arxiv.org/abs/1905.04166 PULP-Platform Project Webpage: https://www.pulp-platform.org/

The Coming Revolution in MEMS Gyroscopes and MEMS Inertial Sensors
Wireless Integrated MicroSensing & Systems - WIMS2 Relevant for automotive robotic drone wearable applications.

Enabling the Next Generation of GPS Technology with Supercorrelation with Dr Ramsey Faragher
Royal Institute of Navigation Focal Point Positioning have developed a new method for processing GNSS radio signals called Supercorrelation which dramatically improves the performance of the earliest stage of radio processing. The software update removes multipath interference at the correlator level, and provides the ability to determine signal arrival angle without adding any new hardware to a standard GNSS device. In this webinar Dr Ramsey Faragher, Founder/CEO of FocalPoint will explain how the technology works, will cover some of the challenges that FocalPoint have overcome in deploying it on very low cost platforms, and will show off the new capabilities that it unlocks. Website: http://rin.org.uk/

AgilLOC Global Navigation Satellite System (GNSS) Anti-Jamming and Spoofing Capability
AgilLOC Antenna Element Compact (AEC) & Resilient Time Source (RTS) provide assured access to Position, Navigation and Timing (PNT) information for mission-critical systems. AEC provides GNSS anti-jam capability under denied environment through adaptive nulling of interference sources. RTS provides add-on GNSS anti-spoof capability and timing resiliency to ensure the integrity of the GNSS.

GRCon20 - Software defined radio based Global Navigation Satellite System real time spoofing....
Software defined radio based Global Navigation Satellite System real time spoofing detection and cancellation Presented by Jean-Michel Friedt,, D. Rabus and G. Goavec-Merou at GNU Radio Conference 2020 http://gnuradio.org/grcon20 Global Navigation Satellite Systems (GNSS) -- most significantly the Global Positioning System (GPS) -- have become ubiquitous to most daily activities, from positioning and navigation to long range time synchronization or distributed energy production ("smart grid"). While initially developed as a military system hardly accessible to civilians, the advent of Software Defined Radio jamming and spoofing capabilities emphasize the low security of GNSS weak signals emitted from satellites orbiting the Earth 20000 km away. While a properly spoofing signal cannot be detected after a consumer-grade receiver has decoded the radiofrequency signal, addressing at the radiofrequency wave level the signal integrity provides the solution of identifying spoofing with all satellites appearing at the same direction of arrival. This classical beamforming analysis -- Controlled Reception Pattern Antenna (CRPA) with multiple antenna reception and phase analysis -- is demonstrated using commercial, off the shelf software defined radio platform receivers (Ettus Research B210) running the real-time GNSS decoder gnss-sdr based on GNU Radio running on embedded boards such as the Raspberry Pi4.

When GNSS fails, what will you do? - MarRINav!
This webinar, called 'When GNSS fails, what will you do? - MarRINav! ' features presentations and comments form Jonathan Turner (NLA Int.), Dr Alan Grant (GLA), and Dana Goward (RNTF). The webinar provides analysis and insights from Phase 1 of the Maritime Resilience and Integrity of Navigation (MarRINav) project. To download the full transcript of Jonathan's presentation please follow this link: https://rin.org.uk/resource/resmgr/fi... Many thanks to all co-sponsors of this webinar: Resilient Navigation and Timing Foundation, Institute of Navigation, GPS World, The Maritime Executive, and of course the MarRINav project. Website: http://rin.org.uk/

GPS Spoofing and Jamming: Learn how to protect against threats to GNSS systems
Steatite

Securing Positioning & Timing 7: Improving Performance by Augmenting GPS/GNSS
Royal Institute of Navigation The seventh, and final, of a series of webinars from the Securing Positioning & Timing short course. This webinar covers Improving Performance by Augmenting GPS/GNSS. Presented by Prof Terry Moore. Supported by the UK Space Agency. Website: http://rin.org.uk/

GPS/GNSS Spoofing and How To Detect It
GPSPATRON GNSS Interference Issues What is GNSS Spoofing? Spoofing Detection Solution In this video, we describe GNSS spoofing/jamming and how to detect it. GPSPATRON is facilitated to protect GNSS-dependent infrastructure against spoofing/jamming or other GNSS signals anomalies that cause time/position accuracy degradation More about GNSS spoofing detection: http://gpspatron.com/detecting-gnss-... Links: http://rntfnd.org/2018/04/24/5-gps-s... http://www.c4reports.org/aboveusonly... http://www.gpsworld.com/ http://insidegnss.com/ http://www.gps.gov/

Securing Positioning & Timing 1: GPS/GNSS Introduction and Defining PNT System Requirements
Royal Institute of Navigation The first of a series of webinars from the Securing Positioning & Timing short course. This webinar covers GPS/GNSS Introduction and Defining PNT System Requirements. Presented by John Pottle. Supported by the UK Space Agency. Website: http://rin.org.uk/

Geolocation: Locating GPS/GNSS Jamming and Spoofing

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Securing Positioning & Timing 3: Detecting and Characterising GPS/GNSS Jamming & Spoofing
Royal Institute of Navigation The third of a series of webinars from the Securing Positioning & Timing short course. This webinar covers Detecting and Characterising GPS/GNSS Jamming & Spoofing. Presented by Dr Mark Dumville. Supported by the UK Space Agency. Website: http://rin.org.uk/

Securing Positioning & Timing 4: Locating GPS/GNSS Jamming and Spoofing
Royal Institute of Navigation The fourth of a series of webinars from the Securing Positioning & Timing short course. This webinar covers Locating GPS/GNSS Jamming and Spoofing. Presented by Mike Jones. Supported by the UK Space Agency. Website: http://rin.org.uk/

GNSS Jamming - Crowd Sourcing Detection and Geolocation
GNSS Jamming - Crowd Sourcing Detection and Geolocation webinar by InsideGNSS

Harris Corporation - Detect and Locate GPS Jamming with Signal Sentry™ 1000
Harris Corporation The Global Positioning System—GPS—is an essential element of the global information infrastructure. GPS jamming devices are becoming cheaper and more accessible, creating a greater need to protect from a diverse range of threats. Harris Signal Sentry 1000 is a GPS interference detection and geolocation solution. It provides a web-based visualization tool to support timely and effective actionable intelligence.

Software-defined Global Navigation Satellite Systems (GNSS)

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Dr. Carles Fernandez: An Open Source Global Navigation Satellite Systems Software-Defined Receiver
Software Defined Radio Academy GNSS-SDR (see https://gnss-sdr.org) is an open source, software-defined Global Navigation Satellite Systems (GNSS) receiver. This software application takes care of all the digital signal processing chain (from the output of the Analog-to-Digital Converter of a radio-frequency front-end, or from raw sam- ples stored in a file), performing signal acquisition and tracking of the available satellite signals, decoding the navigation message and computing the observables needed by positioning algorithms, which ultimately compute the navigation solution. Several outputs are provided in standard formats, including RINEX observation and navigation files, RTCM-104 v3.2 message streaming via TCP/IP and NMEA-0183, as well as KML, GeoJSON, and GPX files for Geographic Information Systems, map representation and Earth browsers. Currently, the software is able to process GLONASS L1 C/A, GPS L1 C/A, Galileo E1b/c, BeiDou B1I, BeiDou B3I, GLONASS L2 C/A, GPS L2C, GPS L5 and Galileo E5a signals, in all possible combinations, including multi-constellation and multi-frequency configurations. The software leverages on the GNU Radio framework, inheriting multithreading scheduling and a modular, scalable architecture. The software is designed to facilitate the inclusion of new signal processing techniques, offering an easy way to measure their impact in the overall receiver performance under fair conditions, as well as the expansion to other signals.

GRCon20 - Software defined radio based Global Navigation Satellite System real time spoofing....
Software defined radio based Global Navigation Satellite System real time spoofing detection and cancellation Presented by Jean-Michel Friedt,, D. Rabus and G. Goavec-Merou at GNU Radio Conference 2020 http://gnuradio.org/grcon20 Global Navigation Satellite Systems (GNSS) -- most significantly the Global Positioning System (GPS) -- have become ubiquitous to most daily activities, from positioning and navigation to long range time synchronization or distributed energy production ("smart grid"). While initially developed as a military system hardly accessible to civilians, the advent of Software Defined Radio jamming and spoofing capabilities emphasize the low security of GNSS weak signals emitted from satellites orbiting the Earth 20000 km away. While a properly spoofing signal cannot be detected after a consumer-grade receiver has decoded the radiofrequency signal, addressing at the radiofrequency wave level the signal integrity provides the solution of identifying spoofing with all satellites appearing at the same direction of arrival. This classical beamforming analysis -- Controlled Reception Pattern Antenna (CRPA) with multiple antenna reception and phase analysis -- is demonstrated using commercial, off the shelf software defined radio platform receivers (Ettus Research B210) running the real-time GNSS decoder gnss-sdr based on GNU Radio running on embedded boards such as the Raspberry Pi4.

Long Range Navigation (LORAN)

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Quantum Sensors in Navigation

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  • UK Research and Innovation
  • Review of Quantum Navigation | Donghui Feng - IOP Conference Series: Earth and Environmental Science
  • Quantum Sensing Technology Growing Rapidly to Enable Ultra Sensitive Quantum RADARS, Imaging, and Navigation | Rajesh Uppal - International Defence Security & Technology

Typically, the performance of measurement devices is limited by deleterious effects such as thermal noise and vibration. Notable exceptions are atomic clocks, which operate very near their fundamental limits. Driving devices to their physical limits will open new application spaces critical to future DoD systems. Indeed, many defense-critical applications already require exceptionally precise time and frequency standards enabled only by atomic clocks. The Global Positioning System (GPS) and the internet are two key examples. Measurement systems based on atomic physics benefit from the exquisite properties of the atom. Among these are (a) precise frequency transitions, (b) the ability to initialize, control, and readout the atomic state and (c) environmental isolation. In addition, atomic properties are absolute, and do not “drift” over time. In this sense, atoms are self-calibrated, making them ideal for precision sensing. Quantum-Assisted Sensing and Readout (QuASAR) | US Defense Advanced Research Projects Agency (DARPA)

Time & Music

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