ILA 38 Conference October 15, 2009 Designing, Developing, and - - PowerPoint PPT Presentation

October 15, 2009 1

ILA 38 Conference Designing, Developing, and Deploying a Temporary eLoran System.

By Charles Schue With thanks to Nautel, Inc. & Symmetricom, Inc.

2

The Tale of Two Markets

• Traditional Markets: (e)Loran Service Providers
• Aviation; Maritime
• Land Mobile; Location Based
• Time and Frequency
• Emerging “Markets”
• High Profile Events (Olympics)
• Interference Enabled Crime Fighting
• COunterINsurgency (COIN) Operations
• Crisis Contingency Operations

3

Design “Philosophy"

• What possible uses/users are out there?
• Can we serve the existing and forecasted markets at the same

time?

• Can we conserve resources? (personnel; space; utilities)
• Can we build in some measure of flexibility? (“software defined

system”)

• Can we provide some level of “future proofing”? (modularity)
• Can we leverage base technology into several markets? (fixed;

temporary; tactical)

4

Development “Philosophy”

• Find innovative technology and repurpose it
• Move from whole system approach to modular system approach
• Command and Control -> Symmetricom TFE
• Signal Generation & Amplification -> Nautel NL Transmitter
• Transmission
• Existing/fixed antenna
• Existing antennas of opportunity (GWEN)
• Temporary antenna
• Follow incremental development path: proof-of-concept; prototype,

pre-production, production

• KISS principle: reduce user-facing complexity (“it just works”)

5

Two calls. The choice of markets becomes moot. The challenge:

• two proofs of concept

(1) a technology showcase & (2) temporary eLoran site

• rapidly deployable
• reusable

6

Deployment Path 1

• Use existing equipment when possible (TFE; cesiums; receivers)
• Use prototype equipment as required (NL prototype)
• Use USCG Loran Support Unit as test facility

7

Proof-of-Concept Transmitter in Halifax, NS - April 2008

8

Proof-of-Concept Transmitter in Wildwood, NJ – May 2008

9

First pulses into 625-foot TLM: 1100, May 12, 2008

10

11

Deployment Path 2

• Use existing equipment when possible (TFE; cesiums; receivers)
• Use prototype equipment as required (NL prototype)
• An operational antenna may not be available for testing!
• Capable of meeting USCG operational parameters
• Use test rate(s): 8090M, 9960T
• Loran Data Channel (LDC) capable [Eurofix optional]
• Fully deploy and pre-test system prior to “live” testing
• Live test system

12

Symmetricom Timing & Frequency Equipment Suite

13

Nautel (Pre-) Production Transmitter – Front View

14

Pre-Production Transmitter – Front View

15

Pre-Production Transmitter – Rear View

16

eLoran-In-A-Box “ELB” Concept

17

Antenna Simulator Timing, Frequency, & Control Simulated Enclosure NL Series Transmitter Antenna Feedline

18

Possible “eLoran in a Box” Boxes

Miller Building Systems Thermo Bond Shelter One Gichner Alkan

19

Small Footprint Antenna Configurations

REQUIREMENTS Frequency: 100kHz Operating Range: 25 nautical miles (46 km) radius Field Strength: +55 dBuv/m (1124 uv/m peak) at ground level Location: Worldwide Soil Type: Conductivity 1 mS/m, Permittivity 15 Minimal physical size, suitable for rapid deployment. 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.

20

7 5 Foot W hip with 6 x 70 foot Top Loading guys Ground Radials 60 x 60 feet

Transmitter output – into 625 TLM equivalent – 58 kW Input AC power requirement @ 300 PPS – 551 W Input AC power requirement @ 600 PPS – 702 W La= 31uH Ca= 678pf Rr= 0.0287 ohms Rg= 4.248 ohms Lc= 3741.8uH Rc= 2.3ohms Ia= 26.4A peak Peak Voltage= 62KV

21

“Tee” Antenna 60 feet high x 150 feet long Ground Radials 26 x 90 feet and 18 x 135 feet

La= 27uH Ca= 568pf Rr= 0.04 ohms Rg= 2.319 ohms Lc= 4464uH Rc= 2.78 ohms Ia= 21.6 A peak Peak voltage= 60KV Transmitter output – into 625 TLM equivalent – 58 kW Input AC power requirement @ 300 PPS – 487 W Input AC power requirement @ 600 PPS – 573 W

22

La= 10uH Ca= 985pf Rr= 0.0317 Rg= 7.1 ohms Lc= 2572uH Rc= 1.6 ohms Ia= 24 A peak Peak Voltage= 38.7KV Transmitter output – into 625 TLM equivalent – 26 kW Input AC power requirement @ 300 PPS – 573 W Input AC power requirement @ 600 PPS – 747 W

I nverted Cone Antenna 60 x 60 x 60 feet Ground Radials 36 x 60 feet

23

Transmitter output – into 625 TLM equivalent – 14 kW Input AC power requirement @ 300 PPS – 519 W Input AC power requirement @ 600 PPS – 638 W

I nverted Cone 70 x 70 x 70 feet Ground Radials 36 x 70 feet

La= 16uH Ca= 1145pf Rr= 0.0431 Rg= 6.81 ohms Lc= 2202uH Rc= 1.4 ohms Ia= 20.5A peak Peak Voltage= 28.3KV

24

Temporary Antenna - Conceptual

25

Temporary Antenna - Actual

26

Proof of Concept ELB Box

27

One Week Early!

28

Got eLoran?