Presentation Slides

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Ploughshare Patents

Tom Stansell

Tom@Stansell.com

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Background

 With a priority date of 9/1/2003, European patent EP 183019981 was awarded to Tony Pratt and John Owen on 2/1/2012

 The patent is valid in: AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT

LI LU MC NL PL PT RO SE SI SK TR (28 Countries)

 “Note: Within nine months of the publication of the mention of the grant of the

European patent in the European Patent Bulletin, any person may give notice to the European Patent Office of opposition to that patent, in accordance with the

Implementing Regulations” (< 4 months to go?)

 Similar patents have been filed in the US and other countries

 The patent is assigned to: “Proprietor: Secretary of State for Defence,

Porton Down, Salisbury, Wiltshire SP4 OJQ (GB)”

 “*Ploughshare Innovations” has contacted several US GPS companies about licensing this technology

 *Ploughshare Innovations Ltd was incorporated in 2005 as a wholly owned subsidiary of Dstl, the MoD’s research and development division. Company

Number 04401901

 This patent aims directly at use of the GPS III L1C signal

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Slide 2

Patent Cover

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Slide 3

Ploughshare

Brochure

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Slide 4

InsideGNSS Ploughshare Patent List

By permission of InsideGNSS

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Slide 5

Summary of L1C Advantages

 Overcomes multiple deficiencies of C/A signal

 More interoperable with Galileo E1 OS

 Satisfies US/EU Agreement

 Will be on all GPS III satellites

 Significant performance improvements:

 Code and carrier tracking threshold

 Code correlation, interference Protection

L1C is a valuable and important new signal

 Time to first fix

 Data demodulation down to tracking threshold

 Lower code tracking noise

 Less multipath interference

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Slide 6

Value-Ordered Innovations

(Stansell’s Opinion)

1. 75% of power in the pilot Stansell (Betz)

2. Low density parity check (LDPC) FEC

 Ma, Shane, Sklar, Wang, Kasemsri, Zapanta

3. CNAV-2 message structure Kovach (Stansell)

4. TOI with BCH encoding Kovach & Cahn

5. Pilot overlay code frames message and improves correlation properties Cahn

6. The spreading and overlay code designs Rushanan

7. The MBOC (TMBOC) waveform Betz

8. Symbol interleaving Dafesh, Sklar, Wang

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Slide 7

Common Spectral Characteristics

These systems have selected two common center frequencies and essentially equivalent power spectral densities

(PSD)

Plot span is ±20 MHZ about center frequency

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Slide 8

L1C MBOC Spectrum

-60

-65

-70

-75

-80

-85

-90

-95

-20 -15 -10 -5 0 5 10

Offset from Center Frequency (MHz)

15 20

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Slide 9

Linear Scale L1C PSD

0.6

0.5

0.4

BOC(1,1)

0.3

0.2

0.1

MBOC

0.0

-20 -15 -10 -5 0 5 10 15 20

Offset from Center Frequency (MHz)

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Slide 10

Receiver-Relevant Patent Claims

10. A receiver comprising means to process a navigation signal as claimed in claim 9.

9. A navigation signal comprising a ranging signal modulated by a subcarrier modulation signal as claimed in either of claims 7 and 8.

7. A subcarrier modulation signal for modulating a ranging signal of a navigation system, the subcarrier modulation signal comprising time domain multiplexed portions of first and second Binary Offset Carrier,

BOC, signals to produce the subcarrier modulation signal wherein the subcarrier modulation signal is adapted to modulate the ranging signal.

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Slide 11

GPS TMBOC Version of MBOC

1 1 1 0 0 0 1 0 0 1 0 1 1 1 0 0 0 1 0 0 1 0 1 1 1 0 0 0 1 0 0 1 0

GPS TMBOC = 4 BOC(6,1) chips out of every 33 chips

On pilot carrier only with 75% of total power

BOC(1,1) Chip BOC(6,1) Chip

489 ns 81.5 ns

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Slide 12

Questions?

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Slide 13

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