gps positioning

7/23/2019 Gps Positioning

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1

GPS

GPS (Global Positioning System)

(Space Geodesy) GPS

(local)(regional)

(global)GPS

GPS

GPS

GPS

[1996] GPS

GPS

GPS

GPS105 617

[,1997]

()

GPS


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2

Wells et al(1986), Seeber

(1993) ,Leick(1995) Hofmann-Wellenhof et al(1997)

1

GPS NAVSTAR GPS (NAVigation Satellite with Time and Ranging Global

Positioning System)

GPS

1973

(range) GPS (signal)

(resection method)

(clock) GPS

GPS

GPS

(space segment)(control segment)(user segment)

GPS 2420,200

55 1995

4 27GPS

15

GPS L( L1 L2) 10.23 MHz L154 120

L1 L2 (L)()

L1= 1575.42 MHz = 19 cm

L2= 1227.60 MHz = 24 cm


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PRN (pseudo random noise code)

C/A (coarse acquisition)300 m

L11.023 MHzC/A(unencrypted)

P (precise)

30 m10.23 MHz,

L1 L2 P

(encrypted) Y

GPS 1

10.23 MHz

L11575.42 MHz

L2

1227.60 MHz

C/A 1.023 MHz

P 10.23 MHz

P

10.23 MHz

x1x0.1

x154

x120

50 BPS

1 GPS

GPS Colorado Springs Falcon

Colorado Springs, Hawaii, AscensionIsland, Diego Garcia Kwajalein

GPS

GPS

3


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4

[Shank et al, 1994] L

Kalman

(satellite-state estimates)

S

(broadcast ephemeris)

GPS GPS

()

GPS GPS

2 GPS

GPS

(pseudo-range)

(carrier phase)

(bias)

1% 0.1 ms P

30 cm 10 P C/A

3 m [Wells et al, 1986]

GPS

C/AP

19 cm L1

2 mm


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3

Doppler

s(t) s tr() r

rs()

5

rs s

rt( ) ( ) ( )= (1)

GPS

N(integer ambiguity)

(loss of lock)

[CCC1]: Page: 8

3-1[CCC2]: Page: 8

(cycle slip)

GPS

GPSGPS

(PR) t

(c),

PR c t r

s

r

s= ( ) (2)


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GPS T dt

d

6

r rs s

r

s

r

s

r

s

r

s

c d t dt

c t c d dt

= + += +

[( ) ( )]

( ) ( )

c T T= ( )

PR T c d dt t

(3)

(2)(3)

r

s

r

s

r

s( ) ( ) ( ( ) ( )) = (4)

()(N)

rs

r

s

r

s

r

f s

cT f d dt t N ( ) ( ) ( ( ) ( ))= + (5)

(datm)

rs

r

s

r

s

r

s

atm

f

cT f d dt t N d ( ) ( ) ( ( ) ( ))= + + (6)

(differential)

4

GPS

()

GPS

GPS


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4.1

GPS

GPS

GPS

(single point positioning)

(relative positioning)

(baseline)[Wells et al, 1986]

7

dr dbB

(7)

dr

db dr

B

(7)

GPS

(broadcast ephemeris)(precise ephemeris)

2-3 m GPS

GPS

GPS

GPS19921-2m 199410-20cm[Beutler

et al, 1994]19975-10cm[Neilan et al, 1997]

GPS (orbit improvement)[

, 1996]

4.2


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GPS

GPS

GPS GPS

(N)

8

N n= ( )1 610 (8)

n

( S)

S=10 (9)

6Nds

s

GPS

(Ionosphere)(Troposphere)

100 1000

50

(1)

GPS

(TECtotal electron content)


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0.51017 electrons/m25.01017 electrons/m2

(10)tcf

TEC=40 3

2

.

cft(group delay)

P

10 ns (nano seconds)

100 ns

(magnetic storms) 11

[Dixon,1991].

(3-10) L1 L2 GPS dt

GPS

dt t t L L= 1 2 (11)

(40.3TEC/c) A

A dt f fL L= ( )1

2

2

2

2 2

f fL L2 1 (12)

GPS

GPS

GPS

L1/L2

(ionospherically free observable)

0.5 ppm [Dodson et al, 1993]

(2)

9


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11

SA (Selective Availability) A-S

(Anti-Spoofing)

(1) SA (Selective Availability)

SA (-process)

(dithering)(-process) [Georgiadou and Doucet, 1990]

SA C/A

20 m 100 m 30 m

156 m

SA

GPS

(2) A-S (Anti-Spoofing)

A-S GPS L1 L2 P

PW Y

Y

A-SGPS P L2 GPS

A-S L2

(squaring)(cross-correlation)

(code-correlation squaring) P-W (P-W code tracking)

[Ashtech Inc, 1992].

4.4

GPS


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12

(mean offset)(variation)GPS

()

(pattern)

8 mm [Braun et al, 1994]

2 10 cm [Larson, 1994]

GPS ()

GPS

GPS GPS

[Schupler and Clark, 1991] GPS

( Trimble, Rogue Ashtech )

5 GPS

GPS

5.1 GPS

GPS (code

correlation technique) L1

C/A


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13

L1

L1 C/A

L1

P P

L1 L2

A-S L2

P L2 A-S

L2 L2

L2 L2

Magnavox Company

Y P P

L2 L2

Allen Osborne Associates Inc

WP L1 L2

L1 L2 L1

Y L2 (Y2-Y1) C/A C/A + (Y2-Y1) L2

Y1 Y2L2

Ashtech Inc P-W

P W L1 L2 W

PW

W PGPS

L1 C/A Y1 L2 Y2

L2

5.2


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GPS

a, b i(6)a

i b i

14

ai

a

i

a

i

a

i

atm

f

cT f d dt t N d ( ) ( ) ( ( ) ( ))= + + (14)

bi

b

i

b

i

b

i

atm

f

cT f d dt t N d ( ) ( ) ( ( ) ( ))= + + (15)

ab b a( ) ( ) ( )= i i i (16)

(14)(15)(16)

abi

ab ab ab

i

atm

if

cT f d N d ( ) ( ) ( )= + + (17)

(17)(14)

dt

a, b i, j

abij

ab

ij

ab

ij

atm

f

cT N d( ) ( )= + + (18)

d(1 2)

ijabij

ab atm

f

cT d( ) ( )12 12= + (19)

(19)

10 km

L1

10 km L1/L2

L1 L2


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16

a Y a Z a

b Y

ij

b Z

ij

b N

ij

ab

ij

ab

ij

ab

ij

t

a a a

b b b ab

ab

ij

t X t Y t Z

t X t Y t Z t N

t t V

( ) ( ) ( )

( ) ( ) ( ) ( )

[ ( ) ( ) ]( )

Xij ij ij

X

ij

+ + +

+ + +

= +0 (24a)

()

X

ij ab

ij j

a

i

a

Y

ij

Z

ij

a

a

t t f X t X X t X

( )( )

[( ( ) ) ( ( ) )

]= =

+ 0 0

a a

j

a

i

ab

ij

a

j

a

a

j

i

a

a

i

ab

ij

a

j

a

a

j

i

a

a

i

a X c t t

t t

Y

f

c

Y t Y

t

Y t Y

t

t t

Z

f

c

Z t Z

t

Z t Z

t

( ) ( )

( )( )

[( ( ) )

( )

( ( ) )

( )]

( )( )

[( ( ) )

( )

( ( ) )

( )]

= =

+

= =

+

0 0

0

0

0

0

0

0

0

0

(24b)

X

ij abij

b

jb

b

j

ib

b

i

Y

ij

Z

ij

b

b

b

t t

X

f

c

X t X

t

X t X

t( )

( )[

( ( ) )

( )

( ( ) )

( )]= = +

0

0

0

0

ab

ij

b

j

b

b

j

i

b

b

i

ab

ij

b

j

b

b

j

i

b

b

i

t t

Y

f

c

Y t Y

t

Y t Y

t

t t

Z

f

c

Z t Z

t

Z t Z

t

( )( )

[( ( ) )

( )

( ( ) )

( )]

( )( )

[( ( ) )

( )

( ( ) )

( )]

= =

+

= =

+

0

0

0

0

0

0

0

0

(24c)

N

ij ab

ij

ab

ijabt

t

N( )

( )= = 1

A

t t t

t t t

t t t

t t t

t t t

t t

X

ij

Y

ij

Z

ij

X

ik

Y

ik

Z

ik

Xil Yil Zil

X

ij

Y

ij

Z

ij

X

ik

Y

ik

Z

ik

X

il

Y

il

Z

il

b b b

b b b

b b b

b b b

b b b

b b b

=

( ) ( ) ( )

( ) ( ) ( )

( ) ( ) ( )( ) ( ) ( )

( ) ( ) ( )

( ) ( )

1 1 1

1 1 1

1 1 1

2 2 2

2 2 2

2 2

1 0 0

0 1 0

0 0 1

( )t2

1 0 0

0 1 0

0 0 1

(24d)

( a)

(24a)

(i, j, k, l)(t1, t2)

(25a)


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17

X

L

t tabij

ab

ij

=

( ) ( )1 10

(25b)

X

Y

Z

N

N

N

b

b

b

ab

ij

ab

ik

ab

il

=

(25c)

t t

t t

t t

t t

t t

ab

ik

ab

ik

ab

il

ab

il

ab

ij

ab

ij

ab

ik

ab

ik

ab

il

ab

il

( ) ( )

( ) ( )

( ) ( )

( ) ( )

( ) ( )

1 1

0

1 1

0

2 2

0

2 2

0

2 2

0

GPS

6

(topography)(geoid)

(ellipsoid)

6.1 GPS WGS84

GPS

WGS84World Geodetic System, 1984WGS84

Z BIHBureau International de lHeureConventional Terrestrial Pole, CTPXBIH

CTPY

X [Defense Mapping


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ITRF

ITRF ITRF94 ABC

1993.00 ITRF94

VLBISLRDORIS GPS ITRF94

[Boucher et al, 1996]

SLR GPS

VLBISLR GPS

ITRF92 1988.0

NNR-NUVEL1A

ITRF GPS 1992 IGS(International GPS Service for

Geodynamics)ITRF IGS

GPS IGS ITRF

GPS[Boucher and Altamimi, 1996]GPS

GPS

ITRF

6.3 GPS

(orthometric height)

(mean sea level,MSL)

(geopotential number)

[Heiskanen and Moritz, 1984]

19

W gdH H

= = 0 0 C W (26)


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heighting)GPS

GPSGPS

GPS

[Zilkoski et al,

1992]

GPS GPS

21

H h N= (29)

H H h h N N2 1 2 1 2 1( ) = ( ) (30) h GPSN

N

H[Rapp and

Balasubramania, 1992]

GPS

GPS

GPS

7 GPS IGS

GPS

GPS

Epoch'92 IGS (International GPS

Service for Geodynamics) 1992GPS


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22

[Beutler,

1993] IAG (International Association of Geodesy)

IGS 1994 1 1GPS

IGS

()(

)(

) (

)[Mueller, 1991]

IGS 150 GPS

IGS GPS (

)IGS GPS

IGS1-2 m

5-10 cm IGS

ITRF ITRF IERS GPS

ITRF

8

1967 (Geodetic Reference System 1967GRS67)

,

GPS

GPS

WGS84

GPS

GPS

IERS


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23

ITRF

[IERS, 1996]

GRS80

GPS ITRF

GPS

GPS105 617

[,1997]

GPS

GPS

GPS

1.

GPS

2. GPS

3.

4.

GPS

5.

6. GPS

7. GPS


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GPS

1. 8 GPS 105 617

2. GPS

3. ITRF94 (1994)

1997TWD97 (Taiwan Datum

1997)

4. GRS80 (1980

)

5. 2 121E

119E

2TMNE

gps positioning

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