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Spectrum-Secure Communications for Autonomous Uas/Uav Platforms

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Spectrum-Secure Communications for Autonomous Uas/Uav Platforms SPECTRUM‐SECURE COMMUNICATIONS FOR AUTONOMOUS UAS/UAV PLATFORMS Andrew L. Drozd ANDRO Computational Solutions, LLC Advanced Applied Technology Division Rome, NY 26 October 2015 Secure UAS Communications Panel 1 Unclassified // Distribution A: Unlimited Distribution Topics • ANDRO Technology Summary • Background of key technical issues related to UAS/UAV spectrum, safety, security and airspace integration . Potential spectrum contention and management issues Frequencies Used for Remote Control A Typical UAV Link UAS Integration to NAS . Spectrum, Security and RTCA‐228 Relevant Issues • Conclusion 2 ANDRO Technology / Application Spaces C2 (Cross‐layer RF Cyber‐Spectrum RF Resource Exploitation Management & Communications / Cyber Security) (Wireless Anti‐ EMI Avoidance Dynamic Spectrum Hacking) (Coexistence) Access/Sharing Spectrum Pre‐test M&S Detect & Avoid (Spectral Contention) Cyber‐Spectrum Exploitation / Secure Wireless Comms / Cognitive Radio Networking / 3 Trusted Routing Technologies for Autonomous Systems (RF sensor‐edge processing) BACKGROUND • ANDRO has access to AFRL’s Stockbridge Controllable Contested Environment Facility and Griffiss FAA UAS Test Site Rome, NY for communications up/down‐link experiments with large or small UAS/UAV platforms. • Member of Northeast UAS Airspace Integration Research Alliance (NUAIR). • Our overall focus is on assessing, pre‐certifying or assuring the following for C2/CDL, payload data link (VDL) and other future RF comms technologies: – RF spectrum collision/contention – Coexistence – Cyber Security (confidentiality/integrity/availability) – Safety. 4 • Cell phone Daily Users of RF Spectrum • Cordless phone • Garage door opener • Car key remote control • Standard time broadcast • Mobile radio • GPS navigation • Microwave oven • Bluetooth • Wifi • Zigbee • Broadcast television and audio • Vehicle‐speed radar, air traffic radar, weather radar • RFID devices such as active badges, passports, wireless gasoline token, no‐contact credit‐cards, and product tags • Satellite TV broadcast reception; also backend signal dissemination • Toll‐road payment vehicle transponders • Citizen's band radio and Family Radio Service • Radio control, including Radio‐controlled model aircraft and vehicles • Wireless microphones and musical instrument links 5 Amateur Radio/Unlicensed Spectrum Bands: Frequencies Generally Used by Amateur UAVs 6 Frequencies for Remote Control (RC) Activities FCC has reserved frequency bands for RC activities http://www.modelaircraft.org/events/frequencies.aspx 72 MHz: aircraft only (channels 21 through 35) 75 MHz: surface vehicles OLDer 53 MHz: all vehicles, older equipment on 100 kHz spacing Vulnerable to amateur 50.8 to 51 MHz: for all vehicles at 20 kHz spacing radio repeater stations 27 MHz: general use, hobbyists. NEWer 2.4 ‐ 2.485 GHz: Spread Spectrum band for general control 900 MHz, 1.2 GHz, 2.4 GHz, 5.8 GHz: common for video transmission 433 MHz or 869 MHz ‐ directional high‐gain antennas for video at increased range 7 Frequencies for RC Activities (Continued) • Older RC aircraft in the US utilized 72 MHz for comms: . Tx broadcasts using AM or FM with PPM or PCM. A specific channel is used for each aircraft. Use of crystals to set the operating channel in the Rx and Tx. For an aircraft controlled on channel 35 (72.49 MHz), if someone turns their radio on the same channel, the aircraft's control may be compromised, so when flying at RC airfields, there is normally a board that flags used channels to avoid incidents. • Latest Rx use synthesizer technology and are 'locked' to the Tx. For synthesized Rx crystal is not needed, full bandwidth can be used (i.e., 35 MHz). • Newer Tx use spread spectrum technology in the 2.4 GHz frequency for communication allowing pilots to transmit in the same band in proximity to each other with little fear of conflicts, and receivers in this band are virtually immune to most sources of EMI. 8 UAS / Airport Significant Frequencies UAV control, telemetry, and video frequencies: Comms link metrics: • 900 MHz, 1.2 GHz, 2.4 GHz, and 5.8 GHz • 900MHz and 2.4GHz are popular because they have more relaxed FCC a) Data rate is the amount of data transferred, regulations for transmit power and duty cycle measured in bits per second (Bps), also called throughput b) Packet loss is packets received compared to Other UAV frequencies: packets sent, expressed as % • ADS‐B for aircraft below 18,000 feet: 978 MHz and 1.090 GHz • GPS: L1 and L2 at 1.2276 and 1.57542 GHz Airport System frequencies: • Airport air‐to‐ground voice radio, ATM voice radio: 120 –135 MHz (VHF radios) • Airport ground radio: 460 MHz • Griffiss Airport Radars • ASR‐8 (airport ATM radar) is 2.7 –2.9 GHz, 20 MHz wide • SRC LSTAR is L‐band, 1.5 GHz • Doppler weather are L‐band and S‐band: 1‐2 GHz and 2‐4 GHz • The 700 MHz Band – between 698 and 806 MHz ‐‐ is public safety groups: police, fire, emergency services 9 A Typical UAV Link (for RC &Other Data) Uplink is used to control/change flight • Periodic (1‐sec) to adjust flight parameters • ~900 MHz datalink • Messages ~1 kB, 56 kb/sec • Often Spread Spectrum and/or encrypted UAV Telemetry is aircraft flight data • Usually ~900 MHz datalink • Location, velocity, heading, altitude, battery life Uplink: Control Commands Downlink: Telemetry Data Payload data is typically video (digital) Downlink: Payload Data • up to 8 Mbit/sec for high quality video link Ground Control System • Control Tx & telemetry Rx • Video receiver Spectrum Management • Commercial digital video recorder Security Control • RSSI indicator 10 Radio Technical Commission for Aeronautics RTCA SC‐228 Phases / Timeline • Minimum Performance Standards for UAS integration into non‐segregated airspace –establish Detect &Avoid (DAA) and C2 Data Link capability: . Provides the C2 function as the primary use of the spectrum. ITU has identified multiple spectrum band as candidates (L‐Band Terrestrial, C‐Band Terrestrial, SATCOM in multiple bands). Minimum Operational Performance Standards (MOPS) for C2 Data Link: Specify equipment reqt’s for civil UAS; reqt’s in Phase I MOPS: L‐ and C‐Band Terrestrial data links Class A are not part of this TOR; consider reqt’s between the UAS and ground subsystem. Phase II MOPS: SATCOM in multiple bands Consider extended UAS operation in Class D, G, and E airspace; Ground taxiing is not part of this TOR. SC 228 Development Timeline: 12/2013 01/2014 – 06/2015 07/2015 – 06/2016 SC‐228 Whitepaper C2 Data Link MOPS for V&V C2 Data Link MOPS V&V Reqt’s for C2 Data Link for Develop prelim MOPS for Conduct V&V Test Program UAS integration into NAS. L‐Band &C‐Band solutions. 11 RTCA SC‐228 Scope Standards development for civil UAS equipped to operate into Class A airspace under IFR (instrument flight rules) Operational Environment: • UAS transitioning to/from airspace Class A, traversing D/E/G • Extended UAS operations in airspace Class D/E/G The C2 Data Link: standards for Link using • L‐band Terrestrial (960‐1164 MHz) data links Airport environment, low altitude, wideband‐ downlinks 960‐977 MHz – assignments for UA at en route cruising altitudes Need ‐ RF Spectrum for: 980‐1020 MHz – additional assignments to low‐ • Pilot ATC Communications Link (voice, data) altitude UA • UAS control link (telecom [uplink], telemetry [downlink]) • C‐band Terrestrial (5030‐5091 MHz) data links • GPS –determine location Narrowband uplinks; 300kHz channels and • ADS‐B ‐ broadcast position location submultiples (25,50,150) Repetition rates for Modes of Operation AeroMAX (broadband for airports) can be utilized for • Automatic ‐ 10 Hz • Manual ‐ 20 Hz (ITU‐R 643 Report M.2171 Tables streaming data from taxiing UA. 23 and 24). 12 • SATCOM in multiple bands Key Technical Issues in UAS Integration to NAS • FAA identified relevant challenge areas: . Communications . Airspace UAS operations . Unmanned Aircraft . Human system integration 13 Key Issues (Continued) • Airspace UAS Operations . Separation Concepts: Collision Avoidance (CA), Self‐Separation (SS), and Separation Assurance (SA) . Airspace Integration Safety: Risks and failure modes of SA/SS/CA integration, including Cockpit Display of Traffic Information . Sense and Avoid Sensors and Fusion: Use on/off‐board sensors; radars; fusion of EO/IR, radar, SWIR, and ADS‐B . Separation Algorithms: Maneuvering algorithms for avoiding other aircraft, weather, wake vortices, terrain, etc. Availability of Surveillance Data: Impact of existing data on intent/trajectory prediction . Terminal Airspace/Surface Operations: Complex and restrictive environment and responsiveness to ATC. • The Unmanned Aircraft . State Awareness and Real Time Mission Management: Negotiate changes in UAS trajectories based on aircraft operational state . Airframe Certification: Emphasis on structural analysis and reduction in airframe testing . Precise Location and Navigation: Alternative to GPS . UAS Avionics and Control: Means to ensure safety and reliability. 14 The Spectrum and Airspace Integration • RF spectrum . Protected safety RF spectrum for control communications . Cyber secure RF infrastructure FAA‐UAS‐operator . Control data link for given spectrum bands. • SC‐228 relevant issues . Evidence of old technology for link signal/spectrum and their management (narrow band, assigned bands, non‐adaptable, no feedback) . Assumed “equal bandwidth for all” or “bands for thee modes” limits number of users of a frequency band and constraint flexibility of frequency access/usage . Low power spread frequency waveforms not considered at all (will enable
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