Transmission and User Requirements Technology for eloran (eloran 의송신기술및수신기기술 ) - Public Version -

Transcription

1 Shared interest in a more productive tomorrow. Transmission and User Requirements Technology for eloran (eloran 의송신기술및수신기기술 ) - Public Version - Presented by: Mr. Charles Schue, President & CEO Mr. John Hartline, Senior Director, Product Solutions July 14, 2011

2 Low Frequency (LF) Alternative PNT&D Fixed Site Solutions eloran System Representative Requirements Representative Equipment Scenarios for Signal Strength and Accuracy Small Footprint Solutions Tactical, Temporary, Transportable The Future Now! LFPhoenix and Beyond

3 Loran-C PNT service in use in many parts of the northern hemisphere LF APNTD Solutions eloran PNT & Data service aka TerraNav Partially deployed: USA/UK Got eloran? Tactical LF Deployable LF Alternative PNT&D service Loran, eloran, TerraNav, LFPhoenix, new initiatives LFPhoenix Alternative Waveforms Alternative Modulation Schemes High-Speed Data Channel

4 Why eloran (TerraNav)? eloran is NOT simply modernized Loran-C! requires a different timing strategy, control strategy, and new equipment to meet more stringent requirements specifies tighter timing tolerances transmissions are synchronized with respect to UTC (not SAM) employs a data channel for broadcast of application specific data includes Differential eloran monitor stations and ASF maps to provide optimum accuracy in key areas (e.g. marine ports or airports) Unaided Loran-C can never achieve the accuracy and integrity inherent in eloran.

5 Enhanced Loran All the good stuff from Loran-C, plus: New infrastructure & technology State-of-the-Art RF transmitters Three cesium primary reference standards per station Precision time & frequency equipment Whole-station Uninterruptible Power Supply (UPS) Robust telecommunications UTC Synchronization techniques Cs or Rb Primary Reference Standard TWSTT; TWLFTT; GNSS/RNSS GNSS/RNSS monitoring NOT directly coupled or controlled What is eloran?

6 What is eloran (continued)? New operational concepts Time-of-transmission control Differential corrections where applicable All-in-view signals ASF mapping Data messaging channel(s) Loran Data Channel (9 th pulse; 10 th pulse; Eurofix; other) Additional integrity Differential corrections (dloran and/or DGPS) Other communication / navigation messages ComNav solution possible

7 New user equipment Combination eloran/gnss receivers Latest digital technology & small form factor E-field antenna H-field antenna (eliminates p-static ) Can use Chip-Scale Atomic Clocks for Direct Ranging Loran (DRL) Seamless across multiple modes (similar to GNSS) Aviation; maritime; land mobile; location based; time & frequency Autonomous; interoperable; diverse; resilient What is eloran (continued)?

8 Military operations (triple canopy, jamming situations, mountainous regions) Wide-area or localized timing source (+/- 30 ns of UTC) Critical infrastructure protection (ports, harbors, airports, key assets) High-profile events (Olympics) Interference-enabled crime fighting (car theft, border crossings, toll cheating, tracking felons) Heading / Pointing (Compass) Automatic Vehicle Location (AVL) services Submarine communications and navigation UAV / UAS solutions LF APNT&D (Loran, eloran, TerraNav, LFPhoenix ) Uses Irregular Warfare / Counterinsurgency (COIN) Operations

9 Low Frequency (LF) Alternative PNT&D Fixed Site Solutions eloran System Representative Requirements Representative Equipment Scenarios for Signal Strength and Accuracy Small Footprint Solutions Tactical, Temporary, Transportable The Future Now! LFPhoenix and Beyond

10 System Level Representative Loran-C or eloran System

11 System Level Considerations Required coverage accuracy and signal strength Re-use existing stations? Number and location of new stations Complete EEZ coverage? Single or dual rate? GRI selection(s) Transmitter and antenna sizing Sovereign or shared integrity control? Number and location of Monitor and dloran Sites Level of ASF surveying required (ports, harbors, airports) GAARDIAN IDM capability? DGPS capability?

12 Transmit Site Representative Transmitting Site Equipment

13 Transmit Site Considerations Collocate Control Center, Monitor Site, GAARDIAN IDM? Modulation scheme(s): 9 th or 10 th pulse Eurofix Prime power Commercial Generator Whole station UPS? Multilevel telecommunications? Landline, satellite, cellular, RF, LF

14 Control Site Representative Control Center Note: System integrity control monitors and takes OOT station off-air

15 Monitor and/or dloran Site dloran Site: special class of Monitor Site providing localized eloran corrections over surveyed-only solution for ports, harbors, airports, or other key areas. Similar to DGPS. Monitor Site: collects signals and provides Integrity information to Control Site

16 GAARDIIAN IDM GAARDIAN: GNSS Availability, Accuracy, Reliability and Integrity Assessment for Timing and Navigation

17 Representative dloran Sites Chinhae Inchon Kunsan Masan Mokpo Pohang Pusan Tonghaehang Ulsan Yosu ICN GMP CJJ TAE KWJ CJU MMX PUS YNY Note: also good locations for GAARDIAN IDM interference monitoring and reporting.

18 Two-Way Time Transfer Techniques Two-Way Low Frequency Time Transfer (TWLFTT) Two-Way Satellite Time Transfer (TWSTT)

19 Transmit Site Representative Requirements TRANSMITTER Meets or exceeds existing Loran-C and eloran improves accuracy, availability, continuity, and integrity transmitted signal specifications reduces facility size and transportation and installation Small size, weight, and input power requirement costs reduces input power, HVAC, and generator costs; smaller High input power to transmitted power efficiency UPS Instantaneous or near instantaneous module or system switches with no appreciable degradation in transmitted improves accuracy, availability, continuity, and integrity signal parameters No appreciable degradation in transmitted signal parameters with a failure of signal generation or highpower power amplification portions of the transmitter improves accuracy, availability, continuity, and integrity Minimum to no PM (other than air filter replacement) improves availability, continuity Highest signal stability (phase stability, jitter, zerocrossing, droop, etc.) improves accuracy True hot-swappable modules improves availability, continuity Local and remote system- and component-level visibility goes to personnel reductions and ability to remotely through modern IP-based technology troubleshoot equipment/system Capable of advanced signal generation and modulation techniques, such as 9th pulse, 10th pulse, Eurofix, BPSK- future-proofing RC, OFDM, SIM Capable of 700+ PPS future-proofing reduces total cost of ownership (TCO) over the lifecycle Comprehensive 10-year warranty of the equipment

20 Transmit Site Representative Requirements TIMING, CONTROL, MONITORING, MODULATION Precision Timing & Frequency Equipment (TFE), capable of providing +/- 30 ns to UTC (+/- 10 ns with TWSTT) improves accuracy TFE can use and ensemble Cs, Rb, GNSS, RNSS, or TWTT inputs improves accuracy, integrity Multimode receivers capable of monitoring Loran-C, eloran single receiver reduces TCO and logistics tail Ability to modulate 9th pulse, 10th pulse, Eurofix, other future-proofing

21 Monitor Site and User Representative Requirements MONITOR SITE Multimode receivers capable of: - monitoring Loran-C and eloran (TerraNav); - providing dloran and eloran calculations; - providing DGPS positioning and horizontal accuracy protection; - providing ASF calculations; - providing TWLFTT interface; - providing UTC and Time-of-Day monitoring; - providing frequency and 1 PPS output. Ability to demodulate 9th pulse, 10th pulse, and Eurofix. Capable of upgrading to monitor alternative waveforms and modulation techniques. Ability to use E-field, H-field, or combinations of antennae. USER Multipurpose receivers capable of receiving Loran-C and eloran (TerraNav); ability to receive LDC messages (9th, 10th, Eurofix); ability to use E-field, H-field, or combinations of antennae.

22 Representative Solution Example: Transmitter 50 kw NL 20 Nautel NL kw ERP eloran Transmitter 21 st century robust LF transmitter Powerful hot-swappable power amplifiers Very high efficiency Very small footprint Advanced User Interface

23 Representative Solution Example: Transmitter Modular Design Allows for Future Growth

24 Representative Timing & Control Equipment Cesium Beam Primary Reference Standard Time & Frequency Equipment LORSTA & Monitor Site monitor and control Receiver

25 Representative Receiving Equipment UrsaNav recently acquired all Intellectual Property rights of Locus Inc., Crossrate LLC, and Plutargus Combining IP to provide the best solutions for our customers UrsaNav UN-150 eloran Timing Receiver UN-150 eloran timing receiver is the first to meet the stringent ETSI requirements for telecommunications Primary Reference Clocks First and only receiver to maintain smooth timing through failures of individual LORSTAs

26 eloran Timing Receiver Performance ETSI PRC mask UN-150 eloran timing receiver Gold standard GPS timing receiver eloran and GPS timing receivers both meet the ETSI Primary Reference Clock mask Both receivers show equivalent performance

27 Latest Receiver Technology X X We are currently working with a partner to develop a very small footprint combination eloran/gps receiver with a VERY small H-Field antenna (approximately 1.5 x 1.5 inches).

28 Existing Sites Signal Strength Coverage Pohang Kwang Ju Niijima Gesashi 150 kw 50 kw 800 kw 800 kw

29 Existing Sites Accuracy Coverage Pohang Kwang Ju Niijima Gesashi 150 kw 50 kw 800 kw 800 kw

30 New Sites Signal Strength Coverage Pohang Kwang Ju Cheju-do Ullung-do Socheong-do 150 kw 50 kw 50 kw 50 kw 50 kw

31 New Sites Accuracy Coverage - Accufix Pohang Kwang Ju Cheju-do Ullung-do Socheong-do 150 kw 50 kw 50 kw 50 kw 50 kw

32 New Sites Accuracy Coverage - NL Pohang Kwang Ju Cheju-do Ullung-do Socheong-do 150 kw 50 kw 50 kw 50 kw 50 kw

33 New Sites Signal Strength Coverage Pohang Kwang Ju Cheju-do Ullung-do Socheong-do Guleob-do 150 kw 50 kw 50 kw 50 kw 50 kw 50 kw

34 New Sites Accuracy Coverage - Accufix Pohang Kwang Ju Cheju-do Ullung-do Socheong-do Guleob-do 150 kw 50 kw 50 kw 50 kw 50 kw 50 kw

35 New Sites Accuracy Coverage - NL Pohang Kwang Ju Cheju-do Ullung-do Socheong-do Guleob-do 150 kw 50 kw 50 kw 50 kw 50 kw 50 kw

36 Low Frequency (LF) Alternative PNT&D Fixed Site Solutions eloran System Representative Requirements Representative Equipment Scenarios for Signal Strength and Accuracy Small Footprint Solutions Tactical, Temporary, Transportable The Future Now! LFPhoenix and Beyond

37 Small Footprint Solutions REQUIREMENTS Frequency: 100kHz Design Operating Range: 25 nautical miles (46 km) radius Field Strength: Location: +55 db/uv/m (1124 uv/m peak) at ground level Worldwide Soil Type: Conductivity 1 ms/m; Permittivity 15 Minimal physical size, suitable for rapid deployment, tactical, temporary, or transportable requirements. A radiated power level of 10 watts (40 watts peak) is necessary to achieve this range. Soil type has a significant effect on antenna ground loss but minimal effect on propagation. Top loading is typically used with electrically short antennas to optimize effective height and efficiency. Peak antenna voltage is the limiting factor in these applications.

38 Representative Small Footprint Antennae 75-Foot Whip Tee 60x60x60 Inverted Cone 90x90x90 Inverted Cone (Used for Field Test)

39 Representative Small Footprint Antennae

40 Small Footprint Solutions: Field Test Results

41 Small Footprint Solutions: Field Test Results

42 Small Footprint Solutions: Field Test Results

43 Small Footprint Solutions: Field Test Results Prototype Transmitter View Inside Truck Antenna Feed Point

44 Small Footprint Solutions: Field Test Results

45 Small Footprint Solutions: Field Test Results Telescoping Antenna Supports Equipment Truck Antenna Tuning Unit

46 Small Footprint Solutions: Field Test Results 90x90x90 Inverted Cone Antenna

47 Small Footprint Solutions: Field Test Results

48 Spotlight on Jamming Jammer 10 km inside N. Korea Radius of 50 km

49 Spotlight on Jamming 10 W ERP Tactical eloran System 25 NM radius around Seoul

50 Low Frequency (LF) Alternative PNT&D Fixed Site Solutions eloran System Representative Requirements Representative Equipment Scenarios for Signal Strength and Accuracy Small Footprint Solutions Tactical, Temporary, Transportable The Future Now! LFPhoenix and Beyond

51 Alternative Waveforms Improved phase codes Phase codes should average to zero Pseudo-Random Noise (PRN) based phase codes will allow unique identification of a station in a group and will reduce cross-correlation of signals from other stations Waveforms can be improved over traditional Loran-C. Examples of actual on-air transmitted waveforms are shown here. Shorter pulses allow for more navigation pulse, or room for more data. Navigation function is not degraded. Improve crossrate effects. 700 PPS successfully tested. All tests performed on a 625 TLM using a Nautel NL 20 prototype transmitter. 51

52 Alternative Signals Navigation with low-bitrate comms. eloran has proven performance. Separate high-bitrate comms channel (1500 bps or more) Nav and comms possibly transmitted from single antenna Receiver: single box, single antenna LFPhoenix 52

53 Alternative Signals Navigation with high-speed comms (1500 bps or more) Uses same spectrum as Loran-C / eloran 53

54 Alternative Signals f1: Long-range navigation with comms (1500 bps) f2: Short-range navigation with comms (>1500 bps) Nav and comms possibly transmitted from single antenna Receiver: single box, single antenna 54

55 Alternative Modulation: OFDM Current LF communications are typically below 100 bps Dedicating a time slice to communications allows advanced techniques Orthogonal Frequency Division Multiple Access (OFDMA) Allows very efficient time/bandwidth use High data throughput (>1500 bps usable) Robust against impulsive noise Multiple transmitters operating at the same time with no interference Little to no increase in power outside of the khz band, depending on transmitter linearity 55

56 Alternative Modulation: OFDM Large number of orthogonal carriers Typically uses amplitude and phase modulation on each carrier (QAM) Used in modern communications systems due to bandwidth efficiency Longer symbol times decrease bandwidth requirements and increase robustness Use of pilot carriers enhances synchronization and allows the channel to be equalized 56

57 Alternative Modulation: OFDM 805 carriers total 161 carriers per site QAM carrier 78 QPSK carriers 5 BPSK pilot carriers 473 bits/symbol 2838 bps (uncoded) Coding rate of 2/3 could achieve 1892 bps per transmitter Resultant signal has similar bandwidth requirements to the navigation pulse, allowing one transmitter for both signals 57

58 Communication symbols (130 ms) Alternative Modulation: OFDM Noise-like signal, rather than pulsed Signal peaks similar to navigation pulses Long symbol time allows noise to be averaged Navigation pulses 58

59 Additional Information and Contacts Alternatives to the Sky eloran White Paper. Pioneering New Frontiers in Position, Navigation, and Timing White Paper. Low-Frequency (LF) Solutions for Alternative Positioning, Navigation, Timing, and Data (APNT&D) and Associated Receiver Technology paper and presentation. Nautel Brochure. Symmetricom Brochure. An Evaluation of the Effectiveness of Intentional Interference to eloran MITRE.

60 Questions?