`
`
`Ex. PGS 1009
`
`
`
`EX. PGS 1009
`
`
`
`
`
`

`

`United States Patent [19]
`Counsehnan, III
`
`[11]
`[45]
`
`Patent Number:
`Date of Patent:
`
`4,809,005
`Feb. 28, 1989
`
`[54]
`
`MULTI-ANTENNA GAS RECEIVER FOR
`SEISMIC SURVEY VESSELS
`
`[75]
`
`Inventor:
`
`Charles C. Counselman, III, Belmont,
`Mass.
`
`[73]
`
`[21]
`[22]
`
`[63]
`
`[51]
`[52]
`[58]
`[56]
`
`Assignee: Western Atlas International, Inc.,
`Houston, Tex.
`
`Appl. No.: 147,123
`
`Filed:
`
`Jan. 21, 1988
`
`Related US. Application Data
`Continuation of Ser. No. 35,662, Apr. 6, 1987, which is
`a continuation-in-part of Ser. No. 852,016, Apr. 14,
`1986, which is a continuation-in-part of Ser. No.
`353,331, Mar. 1, 1982.
`
`Int. Cl.4 ............................................ .. H04B 7/185
`
`......... .. 342/352; 342/357
`.
`Field of Search ................... .. 342/352, 357; 375/1
`
`References Cited
`U.S. PATENT DOCUMENTS
`
`3,860,921 1/1975 Wood ................................ .. 342/109
`3,900,873 8/1975 Bouvier et a1. .
`342/103
`3,906,204 9/1975 Rigdon et a1. .... ..
`342/357 X
`3,943,514 3/1976 Afendykiw et a1.
`342/156
`4,045,796 8/1977 Kline ......................... ..
`.. 342/103
`4,054,879 10/1977 Wright et a1.
`342/192
`
`4,114,155 9/1978 Raab . . . . . . . . . . . .
`
`. . . .. 342/394
`
`. 342/458
`4,170,776 10/1979 McDoran .
`455/12
`4,232,389 11/1980 Loiler ..... ..
`342/352
`4,368,469 1/1983 Ott et a1. ..
`375/1 X
`4,443,799 4/1984 Rubin ......... ..
`342/357
`4,445,118 4/1984 Taylor et a1.
`375/1 X
`4,455,651 6/1984 Baran ......... ..
`342/460
`4,463,357 7/1984 MacDoran
`342/460
`4,468,793 8/1984 Johnson et a1. ..
`...... .. 375/1
`4,484,335 11/1984 Mosley et a1.
`342/357
`4,578,678 3/1986 Hurd .............. ..
`375/1
`4,601,005 7/1986 Kilvington ..... ..
`342/352
`4,613,864 9/1986 Hofgen ........... ..
`324/420 X
`4,613,977 9/1986 Wong et a1. .
`342/357
`4,652,884 3/1987 Starker ........... .,
`...... .. 375/1
`4,656,642 4/ 1987 Apostolos et a1.
`4,672,382 6/1987 Fukuhara et a1. ................. .. 342/357
`
`.
`
`FOREIGN PATENT DOCUMENTS
`852191 5/1985 Norway .
`
`OTHER PUBLICATIONS
`Charles C. Counselman III, “Radio Astrometry”, An
`nual Reviews of Astrometry and Astrophysics, vol. 14,
`1976, pp. 197-214.
`(List continued on next page.)
`
`Primary Examiner-Theodore M. Blum
`Assistant Examiner—John B. Sotomayor
`Attorney, Agent, or Firm-Norman E. Brunell; E.
`Eugene Thigpen
`ABSTRACT
`[57]
`Method and apparatus are disclosed for accurately de
`termining position from GPS satellites and received on
`a ship using observations of C/A code group delay, L1
`band center frequency carrier phase, L1 band 5.115
`MHz implicit carrier phase, and L2 band 5.115 MHz
`implicit carrier phase. A precise measurement of the
`range to each satellite is made based upon the L1 center
`frequency carrier phase. A correction for ionospheric
`effects is determined by simultaneous observation of the
`group delays of the wide bandwidth P code modula
`tions in both the L1 and L2 bands. These group delays
`are determined by measuring the phases of carrier
`waves implicit in the spread-spectrum signals received
`in both bands. These carriers are reconstructed from
`both the L1 and L2 band signals from each satellite
`without using knowledge of the P code. The unknown
`biases in the L1 center frequency carrier phase range
`measurements are determined from simultaneous,
`pseudorange measurements, with time averaging. The
`instantaneous position of the antenna receiving these
`signals, and therefore the ship, may then be determined
`from the ranges so determined, with both the bias and
`the ionospheric effects having been eliminated. Addi
`tional antennas are positioned on the ship and a seismic
`streamer towed by the ship to reject false signals, com
`pensate for blockage of signals by the ship’s structure,
`and determine the position of sensors in the streamer.
`
`9 Claims, 25 Drawing Sheets
`
`Ex. PGS 1009
`
`

`

`4,809,005
`Page 2
`
`OTHER PUBLICATIONS
`
`Counselman, Shapiro, Greenspan and Cox, “Backpack
`VLBI Terminal with Subcentimeter Capability”,
`NASA Conference Publication 2115-Radio Interfer
`ometry Techniques for Geodesy, 1980, pp. 409-414.
`Counselman, Gourevitch, King, Herring, Shapiro,
`Greenspan, Rogers, Whitney and Cappallo, “Accuracy
`of Baseline Determinations by MITES Assessed by
`Comparison with Tapes, Theodolite, and Geodimeter
`Measurements”, EOS, The Transactions of the Ameri
`can Geophysical Union, vol. 62, Apr. 28, 1981, p. 260.
`Counselman and Shapiro, “Miniature Interferometer
`Terminals for Earth Surveying”, Bulletin Geodesique,
`vol. 53, 1979, pp. 139-163.
`W. 0. Henry, “Some Developments in Loran”, Journal
`of Geophysical Research, vol. 65, Feb. 1960, pp.
`506-513.
`Pierce, “Omega”, IEEE Transactions on Aerospace
`and Electronics Systems, Vol. AES-l, No. 3, Dec.
`1965, p. 206-215.
`J. J. Spilker, Jr., “GPS Signal Structure and Perfor
`mance Characteristics”, Navigations, vol. 25, No. 2,
`1978, pp. 121-146.
`Bossler, Goad and Bender, “Using the Global Position
`ing Systems (GPS) for Geodetic Positioning”, Bulletin
`Geodesique, vol. 54, 1980, pp. 553-563.
`Alan E. E. Rogers, “Broad-Band Passive 90° RC Hy
`brid with Low Component Sensivity for Use in the
`Video Range of Frequencies”, Proceedings of the
`IEEE, vol. 59, 1971, pp. 1617-1618.
`M. L. Meeks, Editor, Methods of Experimental Physics,
`vol. 12, (Astrophysics), Part C (Radio Observations),
`1976, pp. v-ix and as follows: Chapter 5.3: J. M. Moran,
`“Very Long Baseline Interferometer Systems”, pp.
`174-197, Chapter 5.5: J. M. Moran, “Very Long Base
`line Interferometric Observations and Data Reduc
`tion”, pp. 228-260, Chapter 5.6: I. I. Shapiro, “Estima
`tion of Astrometric and Geodetic Parameters”, pp.
`261-276.
`Counselman and Gourevitch, “Miniature Interferome
`ter Terminals for Earth Surveying: Ambiguity and Mul
`tipath with Global Positioning Systems”, IEEE Trans
`actions on Geoscience and Remote Sensing, vol.
`GE-l9, No. 4, Oct. 1981, pp. 244-252.
`Counselman and Shapiro, “Miniature Interferometer
`
`Terminals for Earth Surveying”, Proceedings of the 9th
`GEOP Conference, An International Symposium on
`the Applications of Geodesy to Geodynamics, Oct. 2-5,
`1978, Dept. of Geodetic Science Report No. 280, The
`Ohio State University, 1978, pp. 65-85.
`Peter F. MacDoran, “Satellite Emission Radio Interfer
`ometric Earth Surveying Series-GPS Geodetic Sys
`tem”, Bulletin Geodesique, vol. 53, 1979, pp. 117-138.
`Peter F. MacDoran, “Series-Satellite Emission Radio
`Interferometric Earth Surveying”, Third Annual
`NASA Geodynamics Program Review, Crustal Dy
`namics Project, Geodynamics Research, Jan. 26-29,
`1981, Goddard Space Flight Center, p. 76 (plus) Three
`View Graph Figures entitled: Satellite L-Band Iono
`spheric Calibration (SLIC); Series One-Way Range
`Receiver Simpli?ed Block Diagram; and Series Re
`ceiver Range Synthesis.
`Peter F. MacDoran, “Satellite Emission Range Inferred
`Earth Surveying, Series-GPS”, JPL, presented at
`Defense Mapping Agency Meeting, Feb. 9, 1981, 13 pp.
`MacDoran, Spitzmesser and Buennagel, “Series: Satel
`lite Emission Range Inferred Earth Surveying”, Pres
`ented at the Third International Geodetic Symposium
`on Satellite Doppler Positioning, Las Cruces, N.M.,
`Feb. 1982, 23 pp.
`MacDoran, Spitzmesser and Buennagel, “Series: Satel
`lite Emission Range Inferred Earth Surveying”, Pro
`ceedings of the 3rd International Geodetic Symposium
`on Satellite Doppler Positioning, vol. 2, 1982, pp.
`1143-1164.
`“Operating Manual STI Model 5010 GPS Receiver”,
`Stanford Telecommunications Inc., STI-O &
`M-8707B, Feb. 25, 1980, selected pages as follows: Title
`page, i-iv, l-l, l-3, 2-1 through 2-5, 3-1 through 3-3,
`6-1 through 6-9.
`“Pioneer Venus Project, Differenced Long-Baseline
`Interferometry Experiment, Design Review Docu
`ment”, NASA Ames Research Center, Moffett Field,
`Calif., Jul. 1, 1977, 23 pp.
`C. Goad, “Visit with P. MacDoran, Aug. 6, 1981”,
`Memo to Capt. Bossler, sent to Dr. Counselman, Aug.
`12, 1981, 3 pp.
`Peter F. MacDoran, Statements made at the 3rd Inter
`national Geodetic Symposium on Satellite Doppler
`Positioning, Feb. 1982.
`
`(List continued on next page.)
`
`Ex. PGS 1009
`
`

`

`4,809,005
`Page 3
`
`OTHER PUBLICATIONS
`
`Rogers, C. A. Knight, H. F. Hinteregger, A. R.
`A. E.
`Whitney, C. C. Counselman III, I. I. Shapiro, S. A.
`Gourevitch and T. A. Clark, “Geodesy by Radio Inter
`ferometry: Determination of a 1.24-km Base Line Vec
`tor with S-mm Repeatability”, J. Geophysics. Res., vol.
`83, pp. 325-334, 1978.
`W. E. Carter, A. E. E. Rogers, C. C. Counselman III,
`and I. I. Shapiro, “Comparison of Geodetic and Radio
`Interferometric Measurements of the Haystack-West
`ford Base Line Vector”, J. Geophysics. Res., vol. 85,
`pp. 2685-2687, 1980.
`R. A. Preston, R. Ergas, H. F. Hinteregger, C. A.
`Knight, D. S. Robertson, I. I. Shapiro, A. R. Whitney,
`A. E. E. Rogers, and T. A. Clark, “Interferometric
`Observations of an Arti?cial Satellite”, Science, vol.
`178, pp. 407-409, 1972.
`C. C. Counselman, III and I. I. Shapiro, “Miniature
`Interferometer Terminals for Earth Surveying”, Proc.
`of the 2nd Int.’l Geodetic Symposium of Satellite Dop
`pler Positioning, vol. 2, pp. 1237-1286, 1979, (avail.
`from Appl. Res. Lab., University of Texas, Austin, Tex.
`78758).
`R. J. Anderle, “Application of the NAVSTAR GPS
`Geodetic Receiver to Geodsey and Geophysics”, Naval
`Surface Weapons Center Tech. Rept., No. 80-282, 27,
`pp., 1980.
`J. J. Spilker, Jr., Digital Communications by Satellite,
`Prentice-Hall, Englewood Cliffs, N.J., pp. 302-303,
`1977.
`P. L. Bender, “A Proposal to the National Aeronautics
`and Space Administration for the Support of GPS Sat
`ellite Orbit Determination Using the Reconstructed
`Carrier Phase Method for Tracking”, Quantum Physics
`Division, National Bureau of Standard, Boulder, Colo.,
`pp. l-l2, submitted Aug. 5, 1980.
`Peter L. Bender, National Bureau of Standards, Private
`Communication, 1978.
`C. C. Counselman III, D. H. Steinbrecher, “The Mac
`rometer TM: A Compact Radio Interferometry Termi
`nal for Geodesy with GPS”, Proceedings of the Third
`International Geodetic Symposium on Satellite Dop
`pler Positioning, pp. 1165-1172, Feb. 8-12, 1982.
`C. C. Counselman III, R. J. Cappallo, S. A. Gourevitch,
`R. L. Greenspan, T. A. Herring, R. W. King, A. E. E.
`Rogers, I. I. Shapiro, R. E. Snyder, D. H. Steinbrecher,
`
`and A. R. Whitnet, “Accuracy of Relative Positioning
`by Interferometry with GPS: Double-Blind Test Re
`sults”, Proceedings of the Third International Geodetic
`Symposium on Satellite Doppler Positioning, pp.
`1173-1176, Feb. 8-12, 1982.
`R. L. Greenspan, A. Y. Ng, J. M. Przyjemski, & J. D.
`Veale, “Accuracy of Relative Positioning by Interfer
`ometry with Reconstructed Carrier GPS: Experimental
`Results”, Proceedings of the Third International Geo
`detic Symposium on Satellite Doppler Positioning, pp.
`1177-1198, Feb. 8-12, 1982.
`T. P. Yunck, “An Introduction to Series-X”, Jet Pro
`pulsion Laboratory, California Institute of Technology,
`NASA Contract NAS 7-1000, Nov. 1982.
`Buennagel, MacDoran, Neilan, Spitzmesser & Young,
`“Satellite Emission Range Inferred Earth Survey (Se
`ries) Project: Final Report on Research and Develop
`ment Phase, 1979 to 1983”, JPL Publication 84 16, Mar.
`1, 1984.
`Crow, Bletzacker, Najarian, Purcell, Statman &
`Thomas, “Series-X Final Engineering Report”, JPL
`D-l476, Aug. 1984.
`'
`MacDoran, Whitcomb & Miller, “Cordless GPS Posi
`tioning Offers Sub-Meter Accuracy”, Sea Technology,
`Oct. 1984.
`MacDoran, Miller, Buennagel & Whitcomb, “Cordless
`Systems for Positioning with Navstar-GPS”, First In
`ternational Symposium on Precise Positioning with the
`Global
`Positioning
`System,
`Positioning
`with
`GPS-1985, Apr. 15-19, 1985.
`James Collins, “GPS Surveying Techniques”, ACSM
`Bulletin, Jun. 1985, pp. 17-20.
`Ron L. Hatch, “The Synergism of GPS Code and Car
`rier Measurements”, Proceedings of the Third Interna
`tional Geodetic Symposium on Satellite Doppler Posi
`tioning, pp. 1213-1231, Feb. 8-12, 1982.
`“Proposal for a GPS Geodetic Receiver”, The Johns
`I-Iopkins University Applied Physics Laboratory, Apr.
`980.
`Phil Ward, “An Advanced Navstar GPS Geodetic
`Receiver”, Proceedings of the Third International Geo
`detic Symposium on Satellite Doppler Positioning, pp.
`1213-1231, Feb. 8-12, 1982.
`Javad Ashjaee, “GPS Doppler Processing for Precise
`Positioning in Dynamic Applications”, IEEE Oceans
`’85, Nov. 1985.
`
`Ex. PGS 1009
`
`

`

`US. Patent
`Feb. 28, 1989
`US. Patent Feb. 28, 1989
`
`Sheet 1 of 25
`Sheet 1 0f 25
`
`4,809,005
`4,809,005
`
`in
`
`
`
`\\\\ \\“ ww
`
`\N
`
`Ex. PGS 1009
`
`Ex. PGS 1009
`
`

`

`US. Patent Feb. 28, 1989
`
`Sheet 2 of 25
`
`4,809,005
`
`GPS
`SATELLITE
`
`/2
`
`/5
`
`213
`
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`
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`
`F/G. 2
`
`Ex. PGS 1009
`
`

`

`US. Patent Feb. 28, 1989
`
`Sheet 3 0f 25
`
`4,809,005
`
`ANTENNA
`
`62
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`
`Ex. PGS 1009
`
`

`

`US. Patent Feb. 28, 1989
`
`Sheet 4 0f 25
`
`4,809,005
`
`440 FROM
`FREQ. STD. 28
`
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`
`Ex. PGS 1009
`
`

`

`US. Patent Feb. 28, 1989
`
`Sheet 5 0f 25
`
`4,809,005
`
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`Ex. PGS 1009
`
`

`

`US. Patent Feb. 28, 1989
`
`Sheet 6 of 25
`
`4,809,005
`
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`
`Ex. PGS 1009
`
`

`

`US. Patent Feb. 28, 1989
`
`Sheet 7 0f 25
`
`4,809,005
`
`308 E0 CARRIER PHASE "
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`US. Patent Feb. 28, 1989
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`

`US. Patent Feb. 28, 1989
`
`Sheet 11 0f 25
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`

`US. Patent
`
`Feb. 28, 1989
`
`Sheet 13 0f 25
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`US. Patent
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`

`US. Patent
`
`Feb. 28, 1989
`
`Sheet 15 of 25
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`4,809,005
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`

`US. Patent
`
`Feb. 28, 1989
`
`Sheet 16 of 25
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`

`US. Patent Feb. 28, 1989
`
`Sheet 17 0f 25
`
`4,809,005
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`

`_ US. Patent
`
`Feb. 28, 1989
`
`Sheet 18 of 25
`
`4,809,005
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`Ex. PGS 1009
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`

`

`US. Patent
`
`Feb. 28, 1989
`
`Sheet 19 of 25
`
`4,809,005
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`US. Patent
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`

`US. Patent
`
`Feb. 28, 1989
`
`Sheet 21 of 25
`
`4,809,005
`
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`

`
`
`US. Patent
`
`Feb. 28, 1989
`
`Sheet 22 of 25
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`US. Patent
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`Feb. 28, 1989
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`Sheet 23 of 25
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`US. Patent
`
`Feb. 28, 1989
`
`Sheet 25 of 25
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`4,809,005
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`
`
`1
`
`4, 809,005
`
`2
`
`MULTI-ANTENNA GAS RECEIVER FOR SEISMIC
`SURVEY VESSELS
`
`BACKGROUND OF THE INVENTION
`
`This is a continuation of co-pending application Ser.
`No. 035,662, filed on Apr. 6, 1987, which is a continua-
`tion-in-part of U.S. patent application Ser. No. 852,016
`filed on Apr. 14, 1986 in the name of Charles C. Coun-
`selman III, which itself is a continuation-in-part of U.S.
`patent application Ser. No. 353,331 filed on Mar. 1,
`1982, also filed in the name of Charles C. Counselman
`III.
`
`The present invention relates generally to an im-
`proved method and system for measuring position on
`earth from a moving platform, such as a ship, using
`signals from the NAVSTAR Global Positioning Sys-
`tern satellites, commonly called GPS satellites. In par-
`ticular, the present invention relates to civilian GPS
`receivers, that is, receivers which do not utilize knowl-
`edge of the potentially unavailable P code component
`of the GPS signals to determine position information.
`Conventional civilian GPS receivers utilize simulta-
`neous pseudorange, in other words, group delay obser-
`vations of the C/A code components of the L1 band
`signals received from a plurality of GPS satellites to
`determine position information. A major source of posi-
`tion errors with such conventional GPS receivers is
`multipath. Multipath errors may be reduced by time
`averaging of observations made from a fixed position.
`Conventional time averaging, however, cannot be used
`to improve the accuracy of receivers on ships because
`the resultant position information would relate to the
`average position of the ship during the observation
`period, not the instantaneous position.
`Position errors also result from ionospheric group
`delay effects in such pseudorange measurements. The
`magnitude of the delay encountered by a signal in the
`ionosphere varies with local conditions and cannot be
`predicted with sufficient accuracy to be eliminated from
`position measurements made by GPS receivers. The
`magnitudes of such errors are frequency dependent,
`however, and can be determined from simultaneous
`measurements of signals in different frequency bands. In
`particular, the GPS system was designed so that simul-
`taneous measurement of signals in the L1 and L2 bands
`could be used to determine ionospheric delay. This
`technique is routinely used in military GPS receivers.
`Conventional civilian receivers measure the C/A code
`group delay in the L1 band, but cannot make L2 band
`C/A code group delay measurements because the C/A
`code modulation is not presently applied to signals
`transmitted in the L2 band. Simultaneous measurements
`therefore can not be conveniently made for both L band
`signals.
`In general, conventional civilian receivers are limited
`in accuracy because of their reliance on group delay,
`and because of their requirement for knowledge of a
`code modulating the signals in a GPS band in order to
`measure the group delay of the signals received in that
`band.
`
`The present invention specifically relates to the use of
`civilian GPS receivers utilizing multiple antennas on
`seismic survey ships and on the seismic survey stream-
`ers towed thereby for determining the position of the
`ship as well as the position or shape of the streamer as it
`is towed through water. Conventional seismic survey
`vessels utilize various combinations of satellite and iner-
`
`tial navigation systems to navigate the ship and deter-
`mine the position thereof, but the information deter-
`mined concerning the position and shape of the
`streamer during the survey is often quite limited. Many
`times the information available concerning the actual
`position of the streamer during the survey is limited to
`an observation that a visually identifiable flag flown
`from a tail buoy dragged by the streamer indicates that
`the streamer is being towed directly behind the ship.
`Such indications are useful for determining that the
`streamer has recovered from the effects a major change
`in ship direction, such as a 180° turn, so that recording
`of survey information can continue. These indications,
`however, are not usually sufficient to permit complete
`use of the more sophisticated forms of seismic surveys
`presently being developed, some of which are called
`3-D surveys.
`For these more sophisticated forms of seismic survey
`work, it is desirable to know the exact location of the
`streamer, and its sensors, during the survey so that in-
`formation collected during one part of the survey at a
`particular location may be used to improve or interpret
`information collected at a different
`location during
`another part of the survey or even during another sur-
`vey. In order to utilize such information it is necessary
`to know very accurately the position of the sensors
`detecting the information at the time of the detection.
`
`SUMMARY OF THE INVENTION
`
`5
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`The present invention provides method and appara-
`tus for accurately determining position information
`using signals transmitted by GPS satellites and received
`on moving platforms, such as ships,
`independent of
`knowledge of the P code component of the signals. A
`precise measurement of the ship’s range to each satellite
`is made based upon the L1 center frequency carrier
`phase. A correction for ionospheric effects is deter-
`mined by simultaneous observation of the group delays
`of the wide bandwidth P code modulations in both the
`L1 and L2 bands. These group delays are determined by
`measuring the phases of carrier waves implicit in the
`spread-spectrum signals received in both bands. These
`carriers are reconstructed from both the L1 and L2
`band signals from each satellite without using knowl-
`edge of the P code. The unknown biases in the L1 cen-
`‘ter frequency carrier phase range measurements are
`determined from simultaneous, pseudorange measure-
`ments, with time averaging. The instantaneous position
`of the ship may then be determined from the ranges so
`determined, with both the bias and the ionospheric
`effects having been eliminated.
`In particular, the present invention provides method
`and apparatus for accurately determining position infor-
`mation related to ships and streamers towed thereby,
`using signals transmitted by GPS satellites and received
`by multiple antennas on the ship and the streamer, inde-
`pendent of knowledge of the P code component of the
`signals. The position of each antenna, and or the base-
`lines there between,
`is determined in order to reject
`identified multipath signals, determine ship orientation
`and times of satellite obscuration by shipboard super-
`structure and to determine the positions of antennas
`related to the streamer to accurately determine sensor
`position.
`
`Ex. PGS 1009
`
`Ex. PGS 1009
`
`

`

`3
`
`4,809,005
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`In the drawings wherein like reference numerals rep-
`resent like parts:
`FIG. 1 illustrates a system for determining position
`information using signals received on a ship from GPS
`satellites in accordance with a preferred embodiment of
`the present invention.
`FIG. 2 illustrates a block diagram of a terminal for
`receiving GPS signals that may be used both onboard
`s