What about Velocity/Heading?

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1 Status of PTA Assuring PNT for all & (Different Subject) What about Velocity/Heading? Brad Parkinson Stanford University November 2017 PTA Status and Using Velocity 1

2 US PNT Advisory Board ( PNTAB major defender of current and future PNT techniques/capabilities) Next meeting in Redondo Beach November 2017 PTA Status and Using Velocity 2

Defense WHITE HOUSE Transportation State

Security Joint Chiefs of Staff NASA NATIONAL

Executive Steering Group Co-Chairs: Defense,

Host: Commerce ADVISORY BOARD Sponsor: NASA

3 U.S. Organizational Structure for GPS Governance Represented by Deputy Secretaries Defense WHITE HOUSE Transportation State Interior Agriculture Commerce Homeland Security Joint Chiefs of Staff NASA NATIONAL EXECUTIVE COMMITTEE FOR SPACE-BASED PNT Executive Steering Group Co-Chairs: Defense, Transportation NATIONAL COORDINATION OFFICE Host: Commerce ADVISORY BOARD Sponsor: NASA GPS International Working Group Chair: State Engineering Forum Co-Chairs: Defense, Transportation Ad Hoc Working Groups PTA Status and Using Velocity 3

4 Primary PNTAB Objective: Meet the Obligation of Assured PNT for all Users Therefore our Focus is PTA Program o Protect the radio spectrum + identify + prosecute interferers o Toughen GPS receivers against natural and human interference o Augment with additional GNSS/PNT sources and Techniques We Advocate Three Foundational GNSS Principles: o Transparency - System and Signal definition, FMEA, Timely insight into Operations, Development, Deployment and Threats o Performance Standards:A Clearly written and officially published - Satellite numbers and geometry, Accuracy, Inherent System Integrity etc. o Integrity Establishing methods for independent and timely user notifications of integrity breach PTA Status and Using Velocity 4

5 GPS The Stealth Utility Now a largely hidden foundation of our US infrastructure Economic value to Commercial users over $60B PTA Status and Using Velocity 5

6 Over $65B In Annual Benefits in identified Commercial Areas Hi Productivity - Heavy Reliance on High Precision GPS receivers PTA Status and Using Velocity 6

7 Not in the Economic Analysis: Applications with insufficient quantified benefit information include: Non-vehicle LBS Location Based Services o asset tracking, people and value Maritime navigation GIS applications except for surveying - global GIS market estimated at $10.6 billion Value of GPS as a timing standard and GPS timing use in several sectors Construction other than earth moving Open pit mining Also: Forestry, Health, Education, Weather, Science, Space PTA Status and Using Velocity 7

8 And does not include Non-economic benefits: Safety-of-life Environment Disaster assessment and relief Induced Benefits International benefits Future benefits new Applications PTA Status and Using Velocity 8

Assured Availability of PNT - "PTA" First Action Area of PTA Protect, Toughen, Augment Protect the Clear & Truthful Signal-7 steps o Pre-actions even before interference occurs - Legal/Law

9 Assured Availability of PNT - "PTA" First Action Area of PTA Protect, Toughen, Augment Protect the Clear & Truthful Signal-7 steps o Pre-actions even before interference occurs - Legal/Law Enforcement/FCC: Protect Spectrum/Enact strong Penalties/suppress Jammer sales o Re-actions when interference/spoofing occurs Quick Knowledge of Jamming Area/Pinpoint Location/Apprehend Perpetrator/Prosecute as Appropriate 11/11/17 PTA for PNT - B. Parkinson 9

Adjacent band interference concern Upper band is apparently off the table, but not officially rescinded Original proposal: Convert to terrestrial & transmit 15 kw+, Tested in 2011 - Transmit

10 Adjacent band interference concern Upper band is apparently off the table, but not officially rescinded Original proposal: Convert to terrestrial & transmit 15 kw+, Tested in Transmit 1.58 kw Ligado s proposed minimum tower spacing of 1420, impacted area must be far less than 710 or else impacted area could be, e.g., city-wide (FAA report) PTA Status and Using Velocity 10

11 Ligado Proposal (The Magic Wand) Operate in the MHz block at levels consistent with protecting certified aviation as determined by the FAA (and that analysis indicates a likely operational power range of 9-13 dbw) This has not been accepted by FAA MHz downlink band: implement a -85 dbw/mhz limit Where how close to transmitters? MHz; retain the -100 dbw/mhz limit from MHz; and implement a -85 dbw/mhz limit for MHz but what is the base station power, density, and antenna pattern? PTA Status and Using Velocity 11

12 Validation Testing Sponsored by Ligado o Roberson o NASTCN (NIST?) o PNTAB found major Omissions DOT Adjacent Band Compatibility (ABC) Testing o Considered all Applications o Acquisition/Reacquisition/tracking o Looked at newer signals PTA Status and Using Velocity 12

13 The Top Issue: Protecting Spectrum for High Precision Uses Public Results of Recent DOT Sponsored Testing Regarding Adjacent Band Compatibility/Interference(ABC) (Courtesy of Karen Van Dyke - released in October More to follow from Karen) The US and International Standard of Harmful Interference: Do Not exceed a 1 db increase in the Noise Floor This is about the onset of measurement degradation PTA Status and Using Velocity 13

14 Raw Data What can each class of receiver tolerate? High Performance have wider Bandwidth and Greater Sensitivity High Performance Receivers: At 1530 MHz, -50 dbm exceeds 1 db threshold by a factor of over 20 PTA Status and Using Velocity 14

15 Example Min. Separation Distance vs. Received Power Single Transmitter with Free Space Path Loss At Greatly reduced Ligado Power Levels of 10 Watts, exceed jamming levels by >factor of 20 at 250 meters At Proposed Power Levels of 1584 Watts, exceed jamming levels by >factor of 20 at 2.4 Km High Performance Receivers 1 db exceeded by factor of 10 at 50 dbm PTA Status and Using Velocity 15

16 A slightly Different Look Use-case Analysis by Chris Hegarty et. al.(mitre) Single Ground Transmitter at 1584 Watts (centered at the lowest band/furthest band from GPS) Use typical broadcast/receive antennas Three levels of effects: o 1 db Threshold (onset of accuracy degradation) o Complete Loss of First satellite o Complete Loss of all satellites Consider both distance and altitude of user PTA Status and Using Velocity 16

17 High Performance Receiver totally jammed at about 600 Meters PTA Status and Using Velocity 17

18 Additional Towers Receiver Density at 400 m PTA Status and Using Velocity 18

19 Timing receivers in an Urban environment PTA Status and Using Velocity 19

20 Major Issue: Given Transmitter Power What is the Propagation Model in the real world? All patterns are shaped by transmitting antenna Free space power is proportional to 1/R 2 for single Transmitter Real world is more complex o Reinforcing and attenuating reflections o Multiple, additive Transmitters Communications Assurance and Worst case PNT interference result in very different expectations PTA Status and Using Velocity 20

21 Typical Urban Antenna Power Pattern Plotted around 360 degrees of Azimuth Minimum Power and Most Challenging Communication Link Problem Maximum Power -Maximum Interference Levels Most Challenging for Navigation Systems 99 th Percentile only exceeded 1% of the full azimuth circle Prudent for a Navigation Interference Model Three Wishes - Dr, Parkinson th Percentile Less signal in only 5% of the full azimuth circle Useful as a Com model 21

22 In urban areas the differences can be a factor of 10 (i.e. 10dB) or more Frequently A factor of 10 or more Three Wishes - Dr, Parkinson

23 Real Data - One Azimuth in Las Vegas Massive Loss of Availability for Precision GPS ~ 15 db Many Samples greatly exceed the Free- Space (1/r 2 ) model Measured Data Typical Com Model Green Line We will see: Ligado spacing of 400 meters insures any Precision GPS receiver is well within Jamming Range Three Wishes - Dr, Parkinson

24 So What? - What PNT applications would be within 200 meters of a Ground Transmitter? PTA Status and Using Velocity 24

25 Public Safety: In harm s way Apt to be less than 200 meters away from Transmitter PTA Status and Using Velocity 25

26 High Productivity: In harm s way Apt to be less than 200 meters away from Transmitter PTA Status and Using Velocity 26

27 In Harm s Way: Rapidly growing RPV/UAV applications Both RPV Control and Air Traffic Monitoring depend on GPS probable paths less 400 Meters to Transmitter sites PTA Status and Using Velocity 27

28 In Harm s Way: Agriculture - perhaps the stealthiest Productivity Application PTA Status and Using Velocity 28

29 So What? - What PNT applications (Called Proximity Operations) would be within 200 meters of a Ground Transmitter? Answer: Many particularly involving Emergency Providers and High Precision and Productivity. PTA Status and Using Velocity 29

30 Conclusions from DOT/Mitre study: Tolerable power levels for High Precision Receivers For High-Performance receivers, at 100m, allowable power is 6.5 milliwatts This is less than 1/100,000 of the requested level of 1.5 kilowatts. PTA Status and Using Velocity 30

31 Recent Spectrum Allocation Developments Ligado Proposal Still on Table o Letters to FCC (Ex Parte) o Ligado to present at PNTAB, Nov New Administration Appointees Study of Testing Gaps by DoD and DoT o Possibly to be briefed at PNTAB o Major efforts to suppress results o Apparent Conclusion: DOT Mitre (ABC) study essentially had it right Rumors of sale of Company multi $B PTA Status and Using Velocity 31

32 PNTAB has Requested Ligado Talk include Detailed Proposed Configuration (Spacing/Density, Antenna types, Power levels, Proposed Propagation models incl. reflections etc.) Impacts and Mitigation for: o All Current and Future GNSS signals (US L1M, L1 P/Y, Galileo etc.) o All Modes of PNT Operation (e.g. acq and reacq, moving vehicles etc.) o All Current/Future PNT Applications Especially the Proximity Operations apt to be within 1/10 th of a mile or less of Transmitters Emergency/First Providers e.g. Police/Fire/Ambulance Precision Timing and Survey Autonomous vehicles; e.g. UAVs and RPVs both tracking and control Helicopters Military, Commercial and General Aviation Proposed Open Air verification of critical cases PTA Status and Using Velocity 32

33 Assured Availability of PNT - "PTA" Second Action Area of PTA Protect, Toughen, Augment Toughen User s Receivers to use GNSS o Increase Jam resistance use well established techniques o Diversify - All GNSS signal receivers (with vector feature) 11/11/17 PTA for PNT - B. Parkinson 33

34 Assured Availability of PNT "PTA" 2nd Action Area: Toughening GPS Receivers Basic Hi Quality Receiver Example: Jammer at Capital + Wider Spread Signal (L1C) Line of Sight Distances + Inertial Aiding + Digital Beam Forming Antenna + A/C shading Range 1/6th Mile Effective Areas of 1KW Jammer Against GPS A/J Nibbles PTA Status and Using Velocity 34

35 Toughen - Commercial Offerings PTA Status and Using Velocity 35

36 Toughen Commercial offering in timing receiver PTA Status and Using Velocity 36

satellites All Signals/constellations Worldwide Integrity Monitoring o Use

37 Assured Availability of PNT - "PTA" Three Action Areas: PTA Protect, Toughen, Augment Augment or substitute PNT sources o Densify and Diversify satellites All Signals/constellations Worldwide Integrity Monitoring o Use Complementary PNT Sources e.g. DME, eloran 11/11/17 PTA for PNT - B. Parkinson 37

PNT about to Explode with Opportunities Galileo

Civil signals at two new frequencies GP(t)S (USA)

frequencies 10 New Civil Signals - Included is a

Operational Civil Signal This will provide

Next generation 4 new signals at two new

38 PNT about to Explode with Opportunities Galileo (European) GLONASS (Russia) Next generation 4 new Civil signals at two new frequencies GP(t)S (USA) Next generation 4 new Civil signals at two new frequencies 10 New Civil Signals - Included is a new International Signal called L1C First Operational Civil Signal This will provide Interchangeability for All Navigation Satellite Next generation 4 new signals at two new frequencies Signals And there will be over 60 satellites on orbit! Result: Even Better Accuracy, Availability Compass QZSS (Japan) (Beidou China) PTA Status and Using Velocity 38

QZSS: L1 C/A, L1 SAIF, L2C, L5 Protecting PNT Current and Future is protecting All Signals, not just GPS L1 C/A Harm is

39 State of the Art: Position based on 220 Channel chip: GPS: Simultaneous L1 C/A, L2E, L2C, L5 GLONASS: Simultaneous L1 C/A, L2 C/A, L2 P, L3 CDMA SBAS: Simultaneous L1 C/A, L5 BeiDou: B1, B2 Galileo: Simultaneous L1 BOC, E5A, E5B, E5AltBOC2 QZSS: L1 C/A, L1 SAIF, L2C, L5 Protecting PNT Current and Future is protecting All Signals, not just GPS L1 C/A Harm is not just loss of lock. It is loss of accuracy, that occurs at much lower levels of interference PTA Status and Using Velocity 39

40 Issues being vigorously pursued by the PNTAB: Counter the weak Support for Protecting new GNSS applications for Humanity (which have lead to Improved Productivity, Safety, and Scientific Research) 1. Ligado has argued that precise GNSS applications should not be frequencyprotected since they were not originally authorized 2. All GNSS Not authorized in US Prolonged Bureaucratic foot dragging-now making some progress 3. Space Service Volume: Great agreement reached between NASA and Air Force fine example of interdepartmental cooperation PTA Status and Using Velocity 40

41 Velocity and Heading frequently overlooked parameters GPS 3D velocity accuracy can be readily achievable at the few centimeter/sec level. Examples of Specifications of current offerings: Velocity Accuracy: Horizontal 7 mm/sec Vertical 20 mm/sec PTA Status and Using Velocity 41

42 Heading is derived from differencing two antenna locations with one receiver. (Clark Cohen, et.al. of Stanford demonstrated this in Aircraft about 25 years ago) One Example of current receiver: Heading accuracy (degrees) specified at : H = 0.25/L where L is the separation in meters between the two antennas. o For 100M (~300 foot ship), better than 100 th of a degree. Another Example: PTA Status and Using Velocity 42

43 Precise Heading and Velocity Can be significant help in Vehicle Control (UAVs, Ships, Missiles, Aircraft) Additional observables! And extremely helpful counter to spoofing. PTA Status and Using Velocity 43

44 Maritime Anti-Spoofing example Use of heading and velocity Both fore and aft antennas would receive the same set of stronger spoofing signals Identical resolved position would be a quick indicator Variations in both heading and velocity can be easily sensed with MEMS gyros and accelerometers. After detection, further methods to operate through can be employed: o Dead reckon with inertial o Use directional antenna to null/attenuate in direction of spoofer My View: A strong spoofing signal might deny service, but it should never cause false indication of position for a well-designed Maritime receiver. PTA Status and Using Velocity 44

45 Conclusions Perhaps the greatest widespread threat to PNT users is repurposing of the adjacent spectrum Testing has shown that many of the high precision & High-Value applications will be in harms way. Further GPS filtering would tend to degrade the accuracy and is not feasible as a retrofit The newer GNSSs, not yet authorized (but already extensively used!) may be an even greater risk. Help! - Please write/ your congressman, the Secretary of Transportation, and the FCC PTA Status and Using Velocity 45

46 Questions? PTA Status and Using Velocity 46

47 Conclusions: The Creeping International Obligations (IMHO) Assure PNT for WW users - for Safety Productivity, Convenience and Science o Defend the Spectrum Nurture and strongly support new, innovative uses of GNSS Support Interoperability (& aim for Interchangeability) of all GNSS PTA Status and Using Velocity 47

48 PTA Status and Using Velocity 48

49 Status of FCC Proceeding and Filings Proceeding at FCC is focused on April 2016 Public Notices on Ligado December 2015 proposals at MHz (downlink or base-station to mobile) and and MHz bands (uplink or mobile to base station) band and separately the reallocation of the MHz band for commercial broadband (currently used for NOAA meteorological services, e.g. GOES 16). Recent Ligado June 5, 2017 ex parte and summation filing claims issues have been resolved....devices in every category of the GPS ecosystem would not experience actual harm if Ligado were permitted to deploy a terrestrial network in accordance with the proposed parameters. GPS devices are highly functioning resilient equipment that can easily coexist with the network proposed by Ligado. Aviation interests disagree and a June 20, 2017 ex parte filing noted: The Representatives [ASRI, AIA, Airlines 4 America, Helicopter Association International] countered the false notion raised in recent filings by Ligado, most recently its June 5, 2017, ex parte, that all opposition to its proposed modifications have been fully addressed and consensus reigns. The Representatives underscored that the issues the aviation and aerospace communities raised earlier in their earlier comments and ex parte submissions in these matters regarding Ligado s proposals have largely gone unresolved since last summer. Several issues, including GPS compatibility, interference to SatCom services (Iridium in the adjacent band and Inmarsat), and concerns about reallocation of the MetSat band, remain unresolved. PTA Status and Using Velocity 49

50 Backups and Additional support PTA Status and Using Velocity 50

51 John Stenbit (Chair), MITRE Bradford Parkinson (Vice Chair), Stanford University James E. Geringer (Second Vice Chair), ESRI Thad Allen, Booz Allen Hamilton Penina Axelrad, University of Colorado John Betz, MITRE Dean Brenner, Qualcomm Scott Burgett, Garmin International Joseph D. Burns, Sensurion Aerospace Per K. Enge, Stanford University Martin C. Faga, MITRE Ronald R. Hatch, consultant to John Deere Larry James, Jet Propulsion Laboratory Peter Marquez, Planetary Resources Terence J. McGurn, private consultant (retired CIA) Timothy A. Murphy, The Boeing Company Ruth Neilan, Jet Propulsion Laboratory T. Russell Shields, Ygomi US PNT Advisory Board Gerhard Beutler, International Association of Geodesy (Switzerland) Sergio Camacho-Lara, United Nations Regional Education Center of Science and Space Technology - Latin America and Caribbean (Mexico) Ann Ciganer, GPS Innovation Alliance Arve Dimmen, Norwegian Coastal Administration (Norway) Dana Goward, Resilient Navigation and Timing Foundation Matt Higgins, International GNSS Society (Australia) Refaat M. Rashad, Arab Institute of Navigation (Egypt) Mr. Kirk Lewis, Institute for Defense Analyses (IDA) Dr. Scott Pace, The George Washington University (GWU) Dr. Tom Powell, Aerospace James J. Miller, Executive Director International Members PTA Status and Using Velocity 51

52 Innovation and the GNSS Signal - The creeping Obligation , Civil PNT community exploits GPS signal and system reliability/availability to create applications that go way beyond the original nominal system characteristics, including: o Monitoring Tectonic Plate motion to fractions of an inch in 3 dimensions o Fully automatic landing of Airplanes o Safety of Life - First Providers Red Precision, Wide Band Receivers o Automatic control of land vehicles Cargo Cranes to bulldozers o Robotic Farming and many more These innovations led to estimate by USG of over $55B per year of tangible economic benefits Future Documented Expectation Literally 10s of B$ savings per year o FAA s NextGen is totally dependent on GPS availability o Intelligent Highways Program - GPS has essential role We strongly believe: Any significant degradation to the GPS System that would damage these benefits, Independent of any stated original characteristic, would be greatly detrimental to US and the World interest PTA Status and Using Velocity 52

53 2) Assessing All GNSS Signals Upper Band edge of Proposed Broadband Hi-Power, Terrestrial Transmitters Question: What interference tests or analyses are proposed against all civil GNSS signals? PTA Status and Using Velocity 53

54 Equivalent Power Ratio Broadband at ¼ mile to GPS 5 Broadband Proposal - Niagara ~ 1 Billion Watts (167 feet with 64,750 cubic feet/ second) F e e t GPS Watts (1 Tablespoon of water per second through 5 feet ) Power Ratio of 5 Billion to One PTA Status and Using Velocity 54

55 Maximum Input Power to stay within 1 db limit GPS L1CA All Receiver Categories High Performance Receivers: At 1530 MHz, -50 dbm exceeds 1 db threshold by a factor of over 10 IP at 1dB (dbm) Frq(MHz) PTA Status and Using Velocity 55

56 A Short Checklist of Issues with Testing Sponsored by Ligado 1. Meeting the 1 db Degradation Criteria 2. Assessing All GNSS Signals 3. Assessing all classes of Precision Receivers 4. Fully Understanding the Assumptions behind Analysis and Test Parameters 5. Ensuring Compliance with Authorized Transmitting Power Levels 6. Assessing Phase-out Time for Legacy Equipment Burden of proof should be on the proposers of repurposing - And should Address All User Categories PTA Status and Using Velocity 56

57 PNTAB Recommendations (1) (Letter of 29 August to Sctys. Work and Mendez) 1. Formally Designate GPS as a Critical Infrastructure Sector for the United States o 14 of 16 current CIs deeply dependent 2. Develop a Formal National Threat Model for PNT Applications in Critical Infrastructure o Build on earlier Van Dyke effort at DOT 3. Prevent the Proliferation of Licensed Emitters in GPS Frequency Bands o Threat continues 4. Establish a Nationwide CONUS Back-Up to GPS with Existing Infrastructure (eloran) o Previously accepted by EXCOM, requires refocus PTA Status and Using Velocity 57

58 1) The 1 db C/N 0 Degradation Criterion 1 db C/N 0 is Longstanding International Standard (Consensus at WRC 2012) o Only one contributor to Noise Floor (add scintillation and other sources) o In particular, it is well understood for radar systems - another faint timing signal application. 1 db criterion designed to protect all modes of GPS operation Loss of Lock, but- - o Acquisition is the most fragile and difficult operation o For Precision a major issue is pico-second jitter 1 decibel (db) degradation of carrier-to-noise ratio (C/No) = reducing satellite power by 21%, Impacts are very situationally dependent example aircraft reacquisition problem NTIA, in the past, has defended this standard Any change to 1 db criterion would be reviewed by PNT community and require good justification establish a domestic and international precedent apply to other space systems, domestic and international, including all U.S. government satellite systems. PTA Status and Using Velocity 58

Three Wishes. and an elaboration. For Reception of. Professor Bradford Parkinson Stanford University. (these are my personal views)

Three Wishes. and an elaboration. For Reception of. Professor Bradford Parkinson Stanford University. (these are my personal views) Three Wishes and an elaboration For Reception of Professor Bradford Parkinson Stanford University (these are my personal views) Three Wishes - Dr, Parkinson 2017 1 Good News: World-wide dependency on GNSS