(12) United States Patent
`(12) United States Patent
`Gerein
`Gerein
`
`(10) Patent No.:
`(10) Patent N0.:
`(45) Date of Patent:
`(45) Date of Patent:
`
`US 6,922,167 B2
`US 6,922,167 B2
`J ul. 26, 2005
`Jul. 26, 2005
`
`111111
`
`1111111111111111111111111111111111111111111111111111111111111
`US006922167B2
`US006922167B2
`
`(54) HARDWARE ARCHITECTURE FOR
`(54) HARDWARE ARCHITECTURE FOR
`PROCESSING GALILEO ALTERNATE
`PROCESSING GALILEO ALTERNATE
`BINARY OFFSET CARRIER (ALTBOC)
`BINARY OFFSET CARRIER (ALTBOC)
`SIGNALS
`SIGNALS
`
`(75) Inventor: Neil Gerein, Okotoks (CA)
`(75)
`Inventor: Neil Gerein, Okotoks (CA)
`
`(73) Assignee: European Space Agency, Paris (FR)
`(73) Assignee: European Space Agency, Paris (FR)
`
`( *) Notice:
`( * ) Notice:
`
`Subject to any disclaimer, the term of this
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`U.S.c. 154(b) by 0 days.
`
`(21) Appl. No.: 10/681,689
`(21) Appl. No.: 10/681,689
`(22) Filed:
`Oct. 8, 2003
`(22) Filed:
`Oct. 8, 2003
`(65)
`Prior Publication Data
`Prior Publication Data
`(65)
`
`US 2005/0012664 A1 Jan. 20, 2005
`US 2005/0012664 A1 Jan. 20, 2005
`
`Related US. Application Data
`Related U.S. Application Data
`(60) Provisional application No. 60/487,180, filed on Jul. 14,
`(60) Provisional application No. 60/487,180, ?led on Jul. 14,
`2003.
`2003.
`
`(51)
`Int. CI? ............................ GOlS 5/02; H04B 7/185
`(51) Int. Cl.7 .......................... .. G01S 5/02; H04B 7/185
`(52) U.S. CI. ............................ 342/357.12; 342/357.06;
`(52) US. Cl. .......................... .. 342/357.12; 342/357.06;
`701/213
`701/213
`(58) Field of Search ....................... 342/357.12, 357.06;
`(58) Field of Search ..................... .. 342/357.12, 357.06;
`701/213
`701/213
`
`(56)
`(56)
`
`References Cited
`References Cited
`
`U.S. PATENT DOCUMENTS
`U.S. PATENT DOCUMENTS
`4,894,662 A *
`Counselman .......... 342/357.12
`1/1990
`4,894,662 A * 1/1990 Counselman ........ .. 342/357.12
`4,894,842 A *
`Broekhoven et al. ....... 375/150
`1/1990
`4,894,842 A * 1/1990 Broekhoven et al. ..... .. 375/150
`Fenton et al.
`4/1998
`5,736,961 A
`5,736,961 A
`4/1998 Fenton et al.
`2003/0231580 A1 *
`Martin et al. ............... 370/203
`12/2003
`2003/0231580 A1 * 12/2003 Martin et al. ............. .. 370/203
`2004/0071200 A1 *
`Betz et al. .................. 375/152
`4/2004
`2004/0071200 A1 * 4/2004 BetZ et al. ................ .. 375/152
`
`OTHER PUBLICATIONS
`OTHER PUBLICATIONS
`
`F. Bastide, et al., “Analysis of LS/RS Acquisition, Tracking
`F. Bastide, et aI., "Analysis of LS/RS Acquisition, Tracking
`and Data Demodulation Thresholds" Proceedings of the
`and Data Demodulation Thresholds” Proceedings of the
`
`Institute of Navigation, (ION), GPS, Sep. 2002, pp.
`Institute of Navigation, (ION), GPS, Sep. 2002, pp.
`2196-2207.
`2196—2207.
`
`(Continued)
`(Continued)
`Primary Examiner—Gregory C. Issing
`Primary Examiner-Gregory C. Issing
`(74) Attorney, Agent, or Firm—Cesari and McKenna, LLP
`(74) Attorney, Agent, or Firm-Cesari and McKenna, LLP
`(57)
`ABSTRACT
`ABSTRACT
`(57)
`
`A GNSS receiver tracks the AltBOC (15,10), or composite
`A GNSS receiver tracks the AltBOC (15,10), or composite
`E5a and E5b, codes using hardWare that locally generates
`E5a and E5b, codes using hardware that locally generates
`the complex composite signal by combining separately
`the complex composite signal by combining separately
`generated real and the imaginary components of the com
`generated real and the imaginary components of the com(cid:173)
`plex signal. To track the dataless composite pilot code
`plex signal. To track the dataless composite pilot code
`signals that are on the quadrature channel of the AltBOC
`signals that are on the quadrature channel of the AltBOC
`signal, the receiver operates PRN code generators that
`signal, the receiver operates PRN code generators that
`produce replica E5a and E5b PRN codes and square Wave
`produce replica E5a and E5b PRN codes and square wave
`generators that generate the real and imaginary components
`generators that generate the real and imaginary components
`of the upper and loWer subcarriers, and combines the signals
`of the upper and lower subcarriers, and combines the signals
`to produce a locally generated complex composite code. The
`to produce a locally generated complex composite code. The
`receiver removes the complex composite code from the
`receiver removes the complex composite code from the
`received signal by multiplying the received signal, Which
`received signal by multiplying the received signal, which
`has been downconverted to baseband I and Q signal
`has been doWnconverted to baseband I and Q signal
`components, by the locally generated complex composite
`components, by the locally generated complex composite
`code. The receiver then uses the results, which are correlated
`code. The receiver then uses the results, Which are correlated
`I and Q prompt signal values, to estimate the center fre(cid:173)
`I and Q prompt signal values, to estimate the center fre
`quency carrier phase angle tracking error. The error signal is
`quency carrier phase angle tracking error. The error signal is
`used to control a numerically controlled oscillator that
`used to control a numerically controlled oscillator that
`operates in a conventional manner, to correct the phase angle
`operates in a conventional manner, to correct the phase angle
`of the locally generated center frequency carrier. The
`of the locally generated center frequency carrier. The
`receiver also uses early and late versions of the locally
`receiver also uses early and late versions of the locally
`generated complex composite pilot code in a DLL, and
`generated complex composite pilot code in a DLL, and
`aligns the locally generated composite pilot code With the
`aligns the locally generated composite pilot code with the
`received composite pilot code by minimizing the corre
`received composite pilot code by minimizing the corre(cid:173)
`sponding DLL error signal. Once the receiver is tracking the
`sponding DLL error signal. Once the receiver is tracking the
`composite pilot code, the receiver determines its pseudor
`composite pilot code, the receiver determines its pseudor(cid:173)
`ange and global position in a conventional manner. The
`ange and global position in a conventional manner. The
`receiver also uses a separate set of correlators to align locally
`receiver also uses a separate set of correlators to align locally
`generated versions of the in-phase composite PRN codes
`generated versions of the in-phase composite PRN codes
`With the in-phase channel codes in the received signal, and
`with the in-phase channel codes in the received signal, and
`thereafter, recover the data that is modulated thereon.
`thereafter, recover the data that is modulated thereon.
`
`11 Claims, 11 Drawing Sheets
`11 Claims, 11 Drawing Sheets
`
`30 AW
`
`20
`DOPPLER /_
`REMOVAL
`
`IF
`DOWNCONVERTER —:
`FILTER
`
`22
`CORRELATOR /
`SUBSYSTEM
`
`26 n 11w
`
`COMPOSITE
`cons
`GENERATOR
`
`‘NTEGRATE
`
`AND DUMP
`
`“a 11
`
`CONTROLLER ‘_
`
`1
`
`TQ Delta Exhibit 2006
`DISH Network LLC v. TQ Delta LLC
`IPR2016-01469
`
`

`
`US 6,922,167 B2
`US 6,922,167 B2
`Page 2
`Page 2
`
`OlliER PUBLICATIONS
`OTHER PUBLICATIONS
`
`L. Ries, et aI., "A Softare Simulation Tool for GNSS2 BOC
`L. Ries, et al., “A Softare Simulation Tool for GNSS2 BOC
`Signals Analysis” Proceedings of the Institute of Navigation,
`Signals Analysis" Proceedings of the Institute of Navigation,
`GPS, Sep. 2002, pp. 2225—2239.
`GPS, Sep. 2002, pp. 2225-2239.
`F. Dovis et al., “SDR Technology Applied to Galileo Receiv
`F. Dovis et aI., "SDR Technology Applied to Galileo Receiv(cid:173)
`ers”, Proceedings of the Institute of Navigation, GPS, Sep.
`ers", Proceedings of the Institute of Navigation, GPS, Sep.
`2002, pp. 2566-2575.
`2002, pp. 2566—2575.
`
`G.W. Hein, et al., “Status of Galileo Frequency and Signal
`G.W. Rein, et aI., "Status of Galileo Frequency and Signal
`Design”, Proceedings of the Institute of Navigation, GPS,
`Design", Proceedings of the Institute of Navigation, GPS,
`Sep. 2002, pp. 266—277.
`Sep. 2002, pp. 266-277.
`Hein, Gunther et al, “Status of Galileo Frequency and Signal
`Rein, Gunther et aI, "Status of Galileo Frequency and Signal
`Design,” ION GPS 2002, Sep. 2002.*
`Design," ION GPS 2002, Sep. 2002.*
`Ganguly, Dr. Surnan, “Real—tirne Dual Frequency SoftWare
`Ganguly, Dr. Suman, "Real-time Dual Frequency Software
`Reciever," 2003 IEEE Plans, Apr. 2004, pp. 366-374.*
`Reciever,” 2003 IEEE Plans, Apr. 2004, pp. 366—374.*
`* cited by examiner
`* cited by eXarniner
`
`2
`
`

`
`u.s. Patent
`U.S. Patent
`
`Jul. 26,2005
`J ul. 26, 2005
`
`Sheet 1 0f 11
`Sheet 1 of 11
`
`US 6,922,167 B2
`US 6,922,167 B2
`
`--------5 .
`
`I
`I
`I
`
`I
`-------L----
`
`|------.n-L------- ..
`
`0)
`u
`c:
`0)
`:::J
`10"
`0)
`CI)
`Z
`0::
`a..
`(.)
`-
`0
`ED
`;CC
`
`
`
`3533, 2mm oom=< E B 8283.“, 5332"‘
`c:
`....
`(Q
`0
`E
`...
`:::J
`ti
`CD
`a..
`CI)
`
`~
`u
`s::
`0)"
`::::J cr
`....
`CD
`u..
`
`m?
`
`on
`
`mm.
`
`.....
`0
`N
`
`~N
`..... ::1:
`~
`~
`>-
`~~
`..-W
`-=>
`0
`W
`a:
`u..
`
`0
`.....
`CD
`..-
`
`R ..-......
`
`,.......
`.
`# .UE
`t-'
`~
`~
`
`3
`
`

`
`N
`~
`""'-l
`CJ\
`I--"
`-..N
`N
`\0
`-..CJ\
`rJ'l
`
`e
`
`'"""
`'"""
`o ....,
`N
`~ .....
`'JJ. =(cid:173)~
`
`Ul
`C
`C
`N
`~~
`N
`
`~ :-
`
`~ = ......
`~ ......
`~
`•
`rJl
`d •
`
`1
`
`0.8
`
`0.6
`
`0.4
`
`•
`
`I
`
`.
`
`•
`
`I
`
`•
`
`.
`
`"
`
`I
`
`•
`
`",
`~-····--r·-··--r··--·
`I,
`
`---.--------.~-... -
`
`I, ,
`I
`
`,':
`
`I
`
`/
`
`I
`•
`
`' •••• 1. •••• __ L". ___ •
`
`,
`
`•
`
`I
`
`•
`
`-,.------r-·_·-
`
`I
`
`• • I
`
`I
`
`•
`
`.'
`
`~
`
`--.--.--.~------~.-----~-----
`
`1 "
`
`.'
`
`•
`......
`,., I
`.. ( •• _11 I
`
`", I
`
`I
`
`•
`•
`I
`
`I
`
`I
`
`I
`
`I
`
`• •
`
`•
`
`•
`
`,I
`
`.
`
`:
`
`•
`
`,~'
`,
`
`.,'
`
`',"
`
`•
`•
`•
`
`•
`
`I
`I
`
`I
`I
`
`I
`
`..t----~'~.~~~':~;. ~r. .... l-... .
`. ~ .. -.. ~:: .. -.~ ....... ~-.. ---~.-.. .
`
`.we
`
`........... I •......... .I ............ t. -1-........... ..
`
`---·-f-----·i-·----;~~-----r---
`•
`-.
`
`I
`1
`
`.'
`
`I
`
`·
`
`•
`
`•
`•
`
`•
`I
`
`I
`
`•
`•
`
`,
`•
`
`JO':
`
`•
`,"
`
`'oIi
`1
`:
`
`normalized autocorrelation function for BOC(15,10)
`
`-O.B
`
`-O.S
`
`-0.4
`
`-0.2
`
`0.4
`
`O.S
`
`0.8
`
`1
`
`FIG. 2
`
`delay (chips) ,
`0.2
`
`-0.2
`
`a
`. ~
`
`-0.4,
`
`-o.S
`
`·O.B
`
`·1 ' ·1
`
`------t------~------~------~~------t-----;~------~-------~------~-----
`
`::
`,.
`
`..... •
`
`•
`
`I
`
`: .. ,
`. '
`
`··---·T-··-·-,·--··--r
`
`'
`
`I
`I
`
`"
`
`I
`
`I
`
`", I
`
`_~ •• _ ••• ~ •••••• J
`
`•
`•
`•
`•
`•
`
`•
`•
`•
`•
`
`,
`
`•
`
`•
`•
`I
`
`,
`
`..
`
`I
`
`"~I
`
`I
`
`,
`
`I
`I
`
`..
`
`'-""
`
`o
`0.2
`
`'. -_ .. --.. ---_ .. ~-.. -.- · ~ · . ,
`" . . ... '
`., .
`' ... --.''''-------,,---
`..... , ...... ,-'
`• •
`
`4
`
`

`
`u.s. Patent
`U.S. Patent
`
`Jul. 26,2005
`Jui. 26, 2005
`
`Sheet 3 0f 11
`Sheet 3 of 11
`
`US 6,922,167 B2
`US 6,922,167 B2
`
`mmjOmkzOu
`
`a:::
`W
`...J
`...J
`0
`a;
`t-
`Z
`0
`u
`
`w _
`
`Fe
`
`...
`
`0
`a; ~
`w
`O
`t-
`Ciiw~
`00
`a..° w
`~(,)z
`
`~
`wa..
`~~
`C)O
`wo
`.-z
`Z«
`
`<0
`N
`
`N
`N
`
`~
`
`0
`
`O _
`
`a;~
`Ow
`~tJ
`w>-
`a;t.Il
`a:::al
`O=>
`uCl)
`
`-
`
`4
`
`I ° w
`
`U
`
`(!)
`
`~
`C\I
`
`0
`U
`z
`a;
`w
`a:::
`O02 mmzmmzu /|
`
`~
`«
`U
`(
`0m
`
`0
`N
`
`~-l
`
`~
`~~ 0
`a.. 0
`a..::::;E
`Ow
`o~
`
`O _
`
`-
`
`-------
`
`0
`
`0
`<i:
`
`co
`
`~
`
`<0
`...-
`
`-
`~
`@T\
`MMHJE
`~ a:::
`u. W
`H:
`-~
`u:::
`
`j
`
`"'It
`..-
`
`a:::
`w
`~
`~ w
`> z
`0
`(,)
`z
`~
`0
`0
`
`N ...-
`
`~
`
`~
`M ENE
`~
`~
`
`5
`
`

`
`u.s. Patent
`U.S. Patent
`
`Jul. 26,2005
`Jui. 26, 2005
`
`Sheet 4 0f 11
`Sheet 4 of 11
`
`US 6,922,167 B2
`US 6,922,167 B2
`
`(5
`
`5.2
`'5. -
`
`N
`10
`N
`
`'0
`0.. o
`
`Sic
`
`mvN
`co v
`
`N
`
`ovw
`
`.... o
`.6
`
`o
`1.0
`N
`
`v
`(.) 1 - - - - - - - -1
`
`(
`
`6
`
`

`
`N
`~
`""-l
`CJ\
`I--"
`-..N
`N
`\0
`-..CJ\
`rJ'l
`
`e
`
`'""'"
`'""'"
`0 ....,
`Ul
`~ .....
`'JJ. =-~
`
`~ = :-
`
`Ul
`C c
`N
`~~
`N
`
`~ = .....
`~ .....
`~
`•
`rJl
`d •
`
`FIG. 5
`
`QPllot
`
`I pilot
`
`.a prompt
`
`AND DUMP
`,INTEGRATE I
`518
`
`~( , )
`
`Clbaseband • Ipilot
`
`,
`
`/512
`
`510
`
`I ~( X)
`
`~
`
`Clbaseband
`
`I prompt
`
`Ibaseband • Ipilot
`
`506
`
`Ibaseband • ClPi~t
`
`I"-. A
`\
`
`504
`
`.( X
`
`~
`
`502-,
`
`Ibaseband
`
`7
`
`

`
`N
`~
`-.....l
`CJ\
`I--"
`-..N
`N
`\0
`-..CJ\
`rJ'l
`
`US 6,922,167 B2
`
`e
`
`~
`~ ......
`'JJ. =(cid:173)~
`
`Sheet 6 0f 11
`
`'"""
`'"""
`o .....,
`
`~ = :-
`
`Ul
`C
`C
`N
`~~
`N
`
`Jul. 26, 2005
`
`~ = .....
`~ .....
`~
`•
`rJl
`d •
`
`U.S. Patent
`
`
`
`
`
`
`
`, .... .... .... .... .... .... ..... .... . ....
`
`
`
`
`
`
`
`
`
`·--,-·----~-·---·-r------,-----
`
`•
`
`•
`
`I
`
`•
`
`I
`
`I
`
`· •
`
`•
`
`__ ._J ______ ~ _______ ~ ______ l ____ _
`
`. .
`
`•
`
`I
`
`•
`
`•
`
`•
`
`.
`
`I
`
`I
`
`I
`
`o .OE
`
`0.6
`
`0.4
`
`0.2
`
`delay (chips)
`
`Haze 52. F mid Jo Jo Jo m who.
`
`
`Jo. m.:. m:- Tod
`
`0
`
`
`
`
`
`.... u ..... .... .....
`
`------~------~-----
`
`•
`
`.
`
`•
`
`.
`
`
`
`
`
`
`
`
`
`..... ..... .... .... .... ..... ..... .....
`
`
`
`
`
`
`
`
`
`
`
`.... ..... .... ..... ..... .... .....
`
`
`
`
`
`
`
`FIG. 6
`
`·1
`' _--'-_--I. __ '---_..I..-_.....L-_--'-_---L_----I __ .a.,----I
`.O.B ....
`
`-0.6
`
`-O.B
`
`:.0.2
`
`-0.4
`
`
`
`
`
`.... ..... .... .... .... .... .....
`
`normalized autocorrelation function for R(tau)""cos(2*pi*fs'*tau)
`
`
`
`
`
`I
`
`
`
`
`
` ..... m m m m w W M m m ?nmrmrahvwakzgm 3.“ E528 52225023 32253
`
`
`
`-_ ......... ". ... _ ....... -,. ... _ ... _ ..... -,_ ........ -.. -,. .......
`------4------~-------~------~----
`
`------,------~----
`
`,
`I ,
`, ,
`
`I
`
`,
`
`.
`·
`
`•
`
`,
`
`•
`
`·
`·
`
`
`
`
`
`
`
`
`
`........... .... .... .... .... .... .... .....
`
`
`
`
`
`
`
`
`
`.......... .... ..... .... ....
`
`
`
`
`
`
`
`I
`
`I
`
`•
`
`•
`
`
`
`
`
`
`
`
`
`•
`.
`,
`.:-------:--
`.
`---.--.------.-.----~ .. --.-~--
`
`
`
`
`
`
`
`
`
`..... .... .......... ..... .... .... .... ..... é
`
`.
`.
`· ·
`.
`.
`.
`
`•••••• 1 •••••• J ••••••
`
`
`
`
`
`
`
`·
`·
`·
`,
`·
`
`·0.6
`
`-0.4
`
`·0.2
`
`0.2
`
`0.4
`
`0.6
`
`O.B
`
`1
`
`8
`
`

`
`u.s. Patent
`U.S. Patent
`
`Jul. 26,2005
`J ul. 26, 2005
`
`Sheet 7 0f 11
`Sheet 7 of 11
`
`US 6,922,167 B2
`US 6,922,167 B2
`
`R1
`RJ
`
`R2
`R1
`
`-1
`-1
`
`-1
`-1
`
`1
`l
`
`-1
`-1
`
`1
`1
`
`-1
`-l
`
`1 1
`l
`l
`
`-2
`0
`0
`R1+R2 -2
`R/+Rl
`Rg-R;
`0 -2
`0
`RrR/
`-2
`
`0 2
`O 2
`2 0
`0
`2
`
`FIG. 7
`FIG. 7
`
`9
`
`

`
`N
`~
`-....l
`CJ\
`I--"
`-..N
`N
`\0
`-..CJ\
`\Jl
`
`e
`
`'""'"
`'""'"
`o ....,
`00
`~ .....
`'JJ. =(cid:173)~
`
`~ = :-
`
`Ul
`C
`C
`N
`~~
`N
`
`~ = .....
`~ .....
`~
`•
`rJl
`d •
`
`FIG. 8
`
`0.8
`
`0.6
`
`0.4
`
`delay (chips)
`
`0.2
`
`0
`
`-0.2
`
`-0.4
`
`-0.8
`
`-1
`-1
`
`·---·t------~-------~------~---t------1------~-------~------~-----
`
`I
`
`I
`
`I
`
`•
`
`•
`
`I
`
`I
`
`•
`
`-----y------,-------r-----~--. --,------,------,-------r------r-----
`
`I
`
`I
`
`I
`
`•
`•
`•
`•
`
`I
`
`I
`•
`I
`•
`
`•
`
`I
`I
`I
`I
`
`I
`
`I
`I
`t
`I
`
`f I
`
`I
`
`\.
`
`•
`
`I
`
`I
`
`•
`
`I
`
`I
`
`---~-------~---.--~-----
`
`I
`
`I
`
`•
`
`................. t ............ ; .............. -:-........... ,.,!-............. ~ .. ..
`
`.
`
`·
`·
`
`-----.. ------,------~-------~--.. -.~---
`
`I
`
`I
`
`I
`I
`I
`I
`
`•
`
`I
`
`•
`
`-0.8
`
`-0.6
`
`-0.4
`
`-0.2
`
`o
`
`0.2
`
`0.4
`
`0.6
`
`0.8
`
`----.-.. _----.------j-----
`
`.
`
`•
`
`I
`I
`
`I
`
`.
`
`I
`
`normalized autocorrelation function for R(tau)*sin{2*pi*fs*tau)
`
`10
`
`

`
`u.s. Patent
`U.S. Patent
`
`J ul. 26, 2005
`Jul. 26,2005
`
`Sheet 9 0f 11
`Sheet 9 of 11
`
`US 6,922,167 B2
`US 6,922,167 B2
`
`$31 0
`
`
`
`my? 5.:
`
`o
`c.o
`Lt')
`
`&! ... .... c:: o
`
`um... Flo
`
`FEINNJ
`
`M
`
`mom
`
`... o
`
`C'\I
`Lt')
`Lt')
`
`mmm
`
`'(cid:173)
`(,)
`
`a .UNE
`
`o
`
`Lt')
`Lt')
`
`....
`U r--------J
`
`A/Qm
`(
`
`
`
`/l Nvm
`
`11
`
`

`
`N
`~
`""-l
`CJ\
`I--"
`-..N
`N
`\0
`-..CJ\
`rJ'l
`
`e
`
`'""'"
`'""'"
`o ....,
`'""'" C
`~ .....
`'JJ. =(cid:173)~
`
`~ = :-
`
`Ul
`C
`C
`N
`~~
`N
`
`~ = .....
`~ .....
`~
`•
`rJl
`d •
`
`• (R2-Rl)prompt
`
`• (R1+R2)prompt
`
`FIG. 10
`
`2-R1
`
`1R
`
`Q~-R1
`
`QR1+R2
`
`610
`
`'R1+R2
`
`~ INTEGRATE I
`
`AND DUMP
`
`616
`
`/
`
`+ M614
`I -
`
`-
`
`•
`
`I .(
`
`•
`
`Qbaseband
`
`612
`
`615
`
`· AND DUMP
`I INTEGRATE I
`
`( I ) I
`
`f·
`
`lIo{
`
`•
`
`I baseband
`
`602
`
`604
`
`12
`
`

`
`N
`~
`""-l
`CJ\
`I--"
`-..N
`N
`\0
`-..CJ\
`rJ'l
`
`e
`
`'""'"
`'""'"
`'""'" o ....,
`'""'"
`~ .....
`'JJ. =(cid:173)~
`
`~ = :-
`
`Ul
`C
`C
`N
`~~
`N
`
`~ = .....
`~ .....
`~
`•
`rJl
`d •
`
`FIG. II
`
`Qpuot
`
`Ipilot
`
`• °prompt
`
`INTEGRATE
`
`R*+=514
`
`I ·1 AND DUMP I
`,c518
`
`• Iprompt
`
`AND DUMP I
`-I INTEGRATE
`516
`
`506
`
`Q ~ baseband· 'pllot
`
`I +
`-t I j
`
`f
`
`Ibaseband • Qpilot
`
`504
`
`QR1+R2
`
`Ibaseband • IPilot
`
`502
`
`QR2-R1
`
`IR1+R2
`
`_ (R2-R1)prompt
`
`\--+------l----+t·\--t--j71--~· AND DUMP
`I INTEGRATE I
`
`( I \
`
`616
`
`612
`
`1----... _ (R1+R2)prompt
`
`I -I
`
`, ,
`
`I
`
`°baseband
`
`-I
`
`~
`
`602
`
`baseband
`I
`
`13
`
`

`
`US 6,922,167 B2
`US 6,922,167 B2
`
`CROSS-REFERENCE TO RELATED
`CROSS-REFERENCE TO RELATED
`APPLICATIONS
`APPLICATIONS
`
`5
`
`BACKGROUND OF THE INVENTION
`BACKGROUND OF THE INVENTION
`
`35
`35
`
`1
`1
`HARDWARE ARCHITECTURE FOR
`HARDWARE ARCHITECTURE FOR
`PROCESSING GALILEO ALTERNATE
`PROCESSING GALILEO ALTERNATE
`BINARY OFFSET CARRIER (ALTBOC)
`BINARY OFFSET CARRIER (ALTBOC)
`SIGNALS
`SIGNALS
`
`2
`2
`tional to the misalignment betWeen the local and the
`tional to the misalignment between the local and the
`received PRN codes. The error signal is used, in turn, to
`received PRN codes. The error signal is used, in turn, to
`control the PRN code generator, which shifts the local PRN
`control the PRN code generator, Which shifts the local PRN
`code essentially to minimize the DLL error signal.
`code essentially to minimiZe the DLL error signal.
`The GPS receiver also typically aligns the satellite carrier
`The GPS receiver also typically aligns the satellite carrier
`with a local carrier using correlation measurements associ(cid:173)
`With a local carrier using correlation measurements associ
`ated with a punctual version of the local PRN code. To do
`ated With a punctual version of the local PRN code. To do
`this the receiver uses a carrier tracking phase lock loop.
`this the receiver uses a carrier tracking phase lock loop.
`The present application claims the bene?t of US. Provi
`The present application claims the benefit of U.S. Provi(cid:173)
`A GPS receiver receives not only line-of-sight, or direct
`A GPS receiver receives not only line-of-sight, or direct
`sional Patent Application Serial No. 60/487,180, which was
`sional Patent Application Serial No. 60/487,180, Which Was
`path, satellite signals but also multipath signals, Which are
`10 path, satellite signals but also multipath signals, which are
`10
`filed on Jul. 14,2003, by Neil Gerein for A HARDWARE
`?led on Jul. 14, 2003, by Neil Gerein for A HARDWARE
`signals that travel along different paths and are re?ected to
`signals that travel along different paths and are reflected to
`ARCHITECTURE FOR PROCESSING GALILEO
`ARCHITECTURE FOR PROCESSING GALILEO
`the receiver from the ground, bodies of Water, nearby
`the receiver from the ground, bodies of water, nearby
`ALTERNATE BINARY OFFSET CARRIER (AltBOC)
`ALTERNATE BINARY OFFSET CARRIER (AltBOC)
`buildings, etc. The multipath signals arrive at the GPS
`buildings, etc. The multipath signals arrive at the GPS
`SIGNALS and is hereby incorporated by reference.
`SIGNALS and is hereby incorporated by reference.
`receiver after the direct-path signal and combine With the
`receiver after the direct-path signal and combine with the
`direct-path signal to produce a distorted received signal.
`direct-path signal to produce a distorted received signal.
`15
`This distortion of the received signal adversely affects code
`15 This distortion of the received signal adversely affects code
`synchroniZation operations because the correlation
`synchronization operations because the correlation
`1. Field of the Invention
`1. Field of the Invention
`measurements, which measure the correlation between the
`measurements, Which measure the correlation betWeen the
`The invention relates generally to GNSS receivers and, in
`The invention relates generally to GNSS receivers and, in
`local PRN code and the received signal, are based on the
`local PRN code and the received signal, are based on the
`particular, to receivers that operate With Galileo AltBOC
`particular, to receivers that operate with Galileo AltBOC
`entire received signal—including the multipath components
`entire received signal-including the multipath components
`satellite signals.
`satellite signals.
`20 thereof. The distortion may be such that the GPS receiver
`thereof. The distortion may be such that the GPS receiver
`20
`2. Background Information
`2. Background Information
`attempts to synchronize to a multipath signal instead of to
`attempts to synchroniZe to a multipath signal instead of to
`Global navigation satellite system (GNSS) receivers, such
`the direct-path signal. This is particularly true for multipath
`Global navigation satellite system (GNSS) receivers, such
`the direct-path signal. This is particularly true for multipath
`as GPS receivers, determine their global positions based on
`as GPS receivers, determine their global positions based on
`signals that have code bit transitions that occur close to the
`signals that have code bit transitions that occur close to the
`the signals received from orbiting GPS and other satellites.
`the signals received from orbiting GPS and other satellites.
`times at which code bit transitions occur in the direct-path
`times at Which code bit transitions occur in the direct-path
`signal.
`The GPS satellites, for example, transmit signals using tWo
`The GPS satellites, for example, transmit signals using two
`25 signal.
`25
`carriers, namely, an L1 carrier at 1575.42 MHz and an L2
`carriers, namely, an L1 carrier at 1575.42 MHZ and an L2
`One way to more accurately synchronize the received and
`One Way to more accurately synchroniZe the received and
`carrier at 1227.60 MHz. Each carrier is modulated by at least
`carrier at 1227.60 MHZ. Each carrier is modulated by at least
`the locally-generated PRN codes is to use the "narrow
`the locally-generated PRN codes is to use the “narroW
`a binary pseudorandom (PRN) code, which consists of a
`a binary pseudorandom (PRN) code, Which consists of a
`correlators" discussed in U.S. Pat. Nos. 5,101,416; 5,390,
`correlators” discussed in US. Pat. Nos. 5,101,416; 5,390,
`seemingly random sequence of ones and zeros that periodi(cid:173)
`seemingly random sequence of ones and Zeros that periodi
`207 and 5,495,499, all of which are assigned to a common
`207 and 5,495,499, all of Which are assigned to a common
`cally repeat. The ones and zeros in the PRN code are referred
`cally repeat. The ones and Zeros in the PRN code are referred
`assignee and incorporated herein by reference. It has been
`30 assignee and incorporated herein by reference. It has been
`to as "code chips," and the transitions in the code from one
`to as “code chips,” and the transitions in the code from one
`determined that narroWing the delay spacing betWeen early
`determined that narrowing the delay spacing between early
`to zero or zero to one, which occur at "code chip times," are
`and late correlation measurements substantially reduces the
`to Zero or Zero to one, Which occur at “code chip times,” are
`and late correlation measurements substantially reduces the
`referred to as "bit transitions." Each GPS satellite uses a
`referred to as “bit transitions.” Each GPS satellite uses a
`adverse effects of noise and multipath signal distortion on
`adverse effects of noise and multipath signal distortion on
`unique PRN code, and thus, a GPS receiver can associate a
`unique PRN code, and thus, a GPS receiver can associate a
`the early-minus-Iate measurements.
`the early-minus-late measurements.
`received signal With a particular satellite by determining
`received signal with a particular satellite by determining
`The delay spacing is narrowed such that the noise corre-
`The delay spacing is narroWed such that the noise corre
`which PRN code is included in the signal.
`Which PRN code is included in the signal.
`lates in the early and late correlation measurements. Also,
`lates in the early and late correlation measurements. Also,
`The GPS receiver calculates the difference between the
`The GPS receiver calculates the difference betWeen the
`the narrow correlators are essentially spaced closer to a
`the narroW correlators are essentially spaced closer to a
`time a satellite transmits its signal and the time that the
`time a satellite transmits its signal and the time that the
`correlation peak that is associated With the punctual PRN
`correlation peak that is associated with the punctual PRN
`receiver receives the signal. The receiver then calculates its
`receiver receives the signal. The receiver then calculates its
`code correlation measurements than the contributions of
`code correlation measurements than the contributions of
`distance, or "pseudorange," from the satellite based on the
`many of the multipath signals. Accordingly, the early-minus
`distance, or “pseudorange,” from the satellite based on the
`many of the multipath signals. Accordingly, the early-minus-
`associated time difference. Using the pseudoranges from at
`associated time difference. Using the pseudoranges from at
`40 late correlation measurements made by these correia tors are
`40
`late correlation measurements made by these correlators are
`least four satellites, the receiver determines its global posi
`least four satellites, the receiver determines its global posi(cid:173)
`signi?cantly less distorted than they Would be if they Were
`significantly less distorted than they would be if they were
`tion.
`tion.
`made at a greater interval around the peak. The closer the
`made at a greater interval around the peak. The closer the
`correia tors are placed to the correlation peak, the more the
`correlators are placed to the correlation peak, the more the
`To determine the time difference, the GPS receiver syn(cid:173)
`To determine the time difference, the GPS receiver syn
`adverse effects of the multipath signals on the correlation
`adverse effects of the multipath signals on the correlation
`chronizes a locally generated PRN code with the PRN code
`chroniZes a locally generated PRN code With the PRN code
`45 measurements are minimized. The delay spacing can not,
`in the received signal by aligning the code chips in each of
`in the received signal by aligning the code chips in each of
`measurements are minimiZed. The delay spacing can not,
`45
`however, be made so narrow that the DLL can not lock to the
`the codes. The GPS receiver then determines how much the
`the codes. The GPS receiver then determines hoW much the
`hoWever, be made so narroW that the DLL can not lock to the
`satellite PRN code and then maintain code lock. Otherwise,
`satellite PRN code and then maintain code lock. OtherWise,
`locally-generated PRN code is shifted, in time, from the
`locally-generated PRN code is shifted, in time, from the
`the receiver cannot track the PRN code in the received signal
`the receiver cannot track the PRN code in the received signal
`known timing of the satellite PRN code at the time of
`knoWn timing of the satellite PRN code at the time of
`without repeatedly taking the time to re-Iock to the code.
`Without repeatedly taking the time to re-lock to the code.
`transmission, and calculates the associated pseudorange.
`transmission, and calculates the associated pseudorange.
`The more closely the GPS receiver aligns the locally
`The more closely the GPS receiver aligns the locally- 50
`The L1 carrier is modulated by two PRN codes, namely,
`The L1 carrier is modulated by tWo PRN codes, namely,
`50
`generated PRN code with the PRN code in the received
`generated PRN code With the PRN code in the received
`a 1.023 MHz CIA code and a 10.23 MHz P-code. The L2
`a 1.023 MHZ C/A code and a 10.23 MHZ P-code. The L2
`signal, the more precisely the GPS receiver can determine
`signal, the more precisely the GPS receiver can determine
`carrier is modulated by the P-code. Generally, a GPS
`carrier is modulated by the P-code. Generally, a GPS
`the associated time difference and pseudorange and, in turn,
`the associated time difference and pseudorange and, in turn,
`receiver constructed in accordance with the above(cid:173)
`receiver constructed in accordance With the above
`its global position.
`its global position.
`referenced patents acquires the satellite signal using a
`referenced patents acquires the satellite signal using a
`locally generated C/A code and a locally generated L1
`The code synchroniZation operations include acquisition
`The code synchronization operations include acquisition 55 locally generated CIA code and a locally generated L1
`55
`carrier. After acquisition, the receiver synchroniZes the
`carrier. After acquisition, the receiver synchronizes the
`of the satellite PRN code and tracking the code. To acquire
`of the satellite PRN code and tracking the code. To acquire
`locally generated C/A code and L1 carrier With the C/A code
`locally generated C/ A code and L1 carrier with the C/ A code
`the PRN code, the GPS receiver generally makes a series of
`the PRN code, the GPS receiver generally makes a series of
`and L1 carrier in the received signal, using the narrow
`and L1 carrier in the received signal, using the narroW
`correlation measurements that are separated in time by a
`correlation measurements that are separated in time by a
`correlators in a DLL and a punctual correlator in the carrier
`correlators in a DLL and a punctual correlator in the carrier
`code chip. After acquisition, the GPS receiver tracks the
`code chip. After acquisition, the GPS receiver tracks the
`tracking loop. The receiver may then use the CIA code
`tracking loop. The receiver may then use the C/A code
`received code. It generally makes "early-minus-Iate" corre(cid:173)
`received code. It generally makes “early-minus-late” corre
`60 tracking information to track the L1 and/or L2 P-codes,
`60
`tracking information to track the L1 and/or L2 P-codes,
`lation measurements, i.e., measurements of the difference
`lation measurements, i.e., measurements of the difference
`Which have knoWn timing relationships With the C/A code,
`which have known timing relationships with the CIA code,
`between (i) a correlation measurement associated with the
`betWeen
`a correlation measurement associated With the
`and with each other.
`and With each other.
`PRN code in the received signal and an early version of the
`PRN code in the received signal and an early version of the
`locally-generated PRN code, and (ii) a correlation measure(cid:173)
`In a newer generation of GPS satellites, the L2 carrier is
`locally-generated PRN code, and (ii) a correlation measure
`In a neWer generation of GPS satellites, the L2 carrier is
`ment associated with the PRN code in the received signal
`also modulated by a C/ A code that is, in turn, modulated by
`also modulated by a C/A code that is, in turn, modulated by
`ment associated With the PRN code in the received signal
`and a late version of the local PRN code. The GPS receiver 65
`a 10.23 MHz square wave. The square wave modulated CIA
`and a late version of the local PRN code. The GPS receiver
`65
`a 10.23 MHZ square Wave. The square Wave modulated C/A
`code, which we refer to hereinafter as the "split CIA code,"
`then uses the early-minus-Iate measurements in a delay lock
`then uses the early-minus-late measurements in a delay lock
`code, Which We refer to hereinafter as the “split C/A code,”
`has maximums in its power spectrum at offsets of ±10 MHz
`loop (DLL), which produces an error signal that is propor-
`loop (DLL), Which produces an error signal that is propor
`has maximums in its poWer spectrum at offsets of 110 MHZ
`
`14
`
`

`
`US 6,922,167 B2
`US 6,922,167 B2
`
`5
`
`15
`
`3
`3
`4
`4
`E5a and E5b quadrature carriers are modulated by dataless
`E5a and E5b quadrature carriers are modulated by dataless
`from the L2 carrier, or in the nulls of the power spectrum of
`from the L2 carrier, or in the nulls of the power spectrum of
`pilot signals, and the respective in-phase carriers are modu
`the P-code. The split C/A code can thus be selectively
`the P-code. The split CIA code can thus be selectively
`pilot signals, and the respective in-phase carriers are modu(cid:173)
`lated by both PRN codes and data signals. A GNSS receiver
`lated by both PRN codes and data signals. A GNSS receiver
`jammed, as necessary, without jamming the L2 P-code.
`jammed, as necessary, Without jamming the L2 P-code.
`may track either the E5a codes or the E5b codes in a manner
`may track either the E5a codes or the E5b codes in a manner
`The autocorrelation function associated With the split C/A
`The autocorrelation function associated with the split CIA
`that is similar to the tracking of the split C/A code discussed
`that is similar to the tracking of the split CIA code discussed
`code has an envelope that corresponds to the autocorrelation
`code has an envelope that corresponds to the autocorrelation
`above.
`above.
`of the 1.023 MHZ C/