(12) United States Patent
`US 6,252,544 B1
`(10) Patent N0.:
`
`Hofiberg
`Jun. 26, 2001
`(45) Date of Patent:
`
`USOO6252544B1
`
`
`
`(54) MOBILE COMMUNICATION DEVICE
`
`(76)
`
`( * ) Notice:
`
`Inventor: Steven M. Hofi'berg, 29 Buckout Rd.,
`West Harrison NY (US) 10604
`’
`Subject to any disclaimer, the term of this
`Patent is extended or adjusted under 35
`1
`V
`,
`use. 154(b) by 0 days
`
`(21) APPL N05 09/236,184
`(22)
`Filed:
`Jan. 25 1999
`’
`Related US. Application Data
`Provisional application No. 60/072,757, filed on Jan. 27,
`1998.
`
`(60)
`
`7
`
`"""""""""""""""""""""""""""" H04B 7/185
`
`Int' Cl'
`(51)
`V
`,
`f)
`(54) U-S- Cl-
`
`342/357-1; 342/357.06;
`342357.13; 342/457; 701/208; 701/213
`(58) Field of Search ............................... 342/457, 357.06,
`342/357.1, 357.13, 357.07; 701/207, 208,
`213
`
`(56)
`
`References Cited
`
`U~S- PATENT DOCUMENTS
`3401,53
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`.
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`
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`
`8V1 ...............
`33:; gmhd~~~~~~~~~~~ 3233(2)?
`,
`’
`
`’ 364%:5ii2:
`$133? 34:12:11,:
`
`8/1991 Daniella-al..
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`. 45554.1
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`..
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`
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`4,552,456
`4,626,850
`1,233,122
`"
`’
`1333313
`59043036
`5:119:504
`5,162,997
`5,189,612
`5,189,619
`5,218,620
`5,223,844 *
`
`
`
`
`
`5,285,523
`2/1994 TakahaShi
`--
`..... 395/22
`5,299,132
`3/1994 Wortham
`364/460
`
`5.301308
`4/1994
`{iratfl
`..... 455/78
`
`5,369,588
`11/1994
`{ayami et al.
`364/449
`
`5,382,957
`1/1995 Binnie ...........
`1. 342/43
`574597667 * 10/1995 Od'dg'dki “1 “L ~~
`364/444
`10/199: SChlage‘ 81‘ al' "
`""" 34057:
`274617265
`,473, 38
`12/199
`:ujita et a .
`364/424.0
`
`.. 364/436
`)ctcrson .
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`6/1996
`
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`340/903
`5,541,590
`
`{ennedy et al.
`.. 379/59
`5,544,225
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`
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`5,563,607
`342/357
`
`5,568,390
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`{irota et al.
`364/449
`
`5’600’561
`2/199: Okamura """"
`364/460
`{aagenstad et al.
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`364/436
`
`364/4442
`5,610,821
`3/1997 Gazis el al.
`
`7
`7
`.
`4/1997 Bednarek et al.
`.. 380/20
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`
`
`4/1997 Loomis et al. ............ 379/58
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`5/1997 eran et al.
`..
`. 455/54.1
`5,630,206
`
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`51/1997
`)inkins
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`
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`342/450
`5,646,612
`7/1997 Byon
`340/903
`5,668,880
`9/1997
`‘
`.. 380/49
`5,673,305
`9/1997
`..... 379/58
`
`5,678,182
`10/1997 Miller ct al.
`. 455/33.1
`
`.. 379/59
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`.
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`
`
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`342/357
`5,691,724
`11/1997 Aker .......
`342/104
`(List continued on next page.)
`.
`.
`Pm’mry Exammgr—Thomas H Tare“
`ASSiSW’” Examiner—D310 L Phan
`(74) Attorney; Agent;
`or Firm—M11616, Hofiberg &
`Macklin, LLP
`
`ABSTRACT
`(57)
`~
`~
`~
`A mobile communications device comprising a location
`sensrng system, producrng a location output; a memory,
`storing a set of locations and associated events; a telecom-
`munications device, communicating event and location
`information between a remote system and said memory; and
`a processor, processing said location output in conjunction
`With said stored locations and associated events in said
`memory, to determine a priority thereof.
`
`43 Claims, 2 Drawing Sheets
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`K-40 Electronics, LLC Exhibit 1002, page 1
`
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`K-40 Electronics, LLC Exhibit 1002, page 1
`
`

`

`US 6,252,544 B1
`
`Page 2
`
`us. PATENT DOCUMENTS
`
`12/1997 Schuchman Ct 211.
`. 375/204
`5,701,328
`
`J
`1 1111f
`1', et a .
`2
`7
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`,
`-- 322223
`23:22? * 2133:
`:0k0113’a}“3 --1
`9
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`’
`'
`5,838,237
`11/1998 Revell et a1.
`..
`340/573
`.. 701/209
`5,845,227
`12/1998 Peterson .....
`
`5,862,509
`1/1999 Desai et al.
`.
`. 701/209
`
`5,914,654
`5,916,300 *
`5 955 973 *
`7
`7
`5983158
`5987381
`
`6/1999 Smith ................................... 340/438
`
`6/1999 Kirk el al.
`701/213
`9/1999 Anderson
`340/988
`
`'
`.
`11/1999 Suzuki el al.
`701/209
`/
`v
`......
`..
`”1999 05mm”
`701/209
`
`* cilcd by examiner
`
`K-40 Electronics, LLC Exhibit 1002, page 2
`
`K-40 Electronics, LLC Exhibit 1002, page 2
`
`

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`K-40 Electronics, LLC Exhibit 1002, page 3
`
`

`

`US. Patent
`
`Jun. 26, 2001
`
`Sheet 2 0f 2
`
`US 6,252,544 B1
`
`Proximity 101
`
`Prospective
`Conjunction 102
`
`
`
`Type of event 103
`
`Type of event and
`sensed condition
`104
`
`W1
`
`W2
`
`W3
`
`Fig. 2
`
`Unit D 201
`
`Location
`202
`
`High
`priority
`messages
`204
`
`Itinerary
`205
`
`Memory dump
`string 206
`
`
`Fig. 3
`
`Event 301
`
`Location 302
`
`Time 303
`Source 304
`
`Expiration 305
`
`Reiiability 306
`Message 307
`
`_
`
`K-40 Electronics, LLC Exhibit 1002, page 4
`
`K-40 Electronics, LLC Exhibit 1002, page 4
`
`

`

`US 6,252,544 B1
`
`1
`MOBILE COMMUNICATION DEVICE
`
`The present application claims the benefit of priority
`from US. Provisional Patent Application Ser. No. 60/072,
`757, the entirety of which is incorporated herein by refer-
`ence.
`
`FIELD OF THE INVENTION
`
`The present invention relates to the field of communica—
`tions devices, and more particularly to mobile telecommu-
`nications devices having position detection and event stor—
`age memory.
`
`BACKGROUND OF THE INVENTION
`
`A number of devices are known which provide mobile
`telecommunication capabilities. Further, known position
`detection systems employ the known Global Positioning
`System (GPS), Global Orbiting Navigational System
`(GLONASS), Loran, RF triangulation, inertial frame refer-
`ence and Cellular Telephone base site, e.g., time difference
`of arrival (TDOA) or nearest antenna proximity systems.
`Known GPS mobile systems include memory to record
`location, time and event type, and some systems may be
`integrated with global information systems, to track path,
`speed, etc. Known Differential GPS (DGPS) systems
`include mobile telecommunication functionality to commu—
`nicate between distant units, typically to allow very precise
`relative position measurements, in the presence of substan—
`tial absolute position errors, or to calibrate the position of a
`mobile transceiver based on a relative position with respect
`to a fixed transceiver having a known location. These
`systems do not typically intercommunicate event informa-
`tion between units. Thus, the communications streams relate
`to position information only. However, known weather
`balloon transceiver systems, for example, do transmit both
`position and weather information to a base station.
`Many electronic location determination systems are
`available, or have been proposed, to provide location infor-
`mation to a user equipped with a location determination
`receiver. Groundbased location determination systems, such
`as Loran, Omega, TACAN, Decca, U.S. Airforce Joint
`Tactical Information Distribution System (JTIDS Relnav),
`or US. Army Position Location and Reporting System
`(PLRS), use the intersection of hyperbolic surfaces to pro—
`vide location information. Arepresentative ground system is
`LORAN—C discussed in LORAN—C User Handbook,
`Department of Transportation, US. Coast Guard, Comman-
`dant Instruction Ml6562.3, May 1990, which is incorpo—
`rated by reference herein. LORAN-C provides a typical
`location accuracy of approximately 400 meters. A limitation
`of a LORAN—C location determination system is that not all
`locations in the northern hemisphere, and n0 locations in the
`southern hemisphere, are covered by LORAN—C. A second
`limitation of [ORAN-(I is that
`the typical accuracy of
`approximately 400 meters is insufficient for many applica-
`tions. A third limitation of LORAN-C is that weather, local
`electronic signal interference, poor crossing angles, closely
`spaced time difference hyperbolas, and skywaves (mnltipath
`interference) frequently cause the accuracy to be signifi—
`cantly worse than 400 meters.
`Other ground-based location determination devices use
`systems that were developed primarily for communications,
`such as cellular telephone, FM broadcast, and AM broad-
`cast. Some cellular telephone systems provide estimates of
`location, using comparison of signal strengths from three or
`more sources. FM broadcast systems having subcarrier
`
`15
`
`40
`
`60
`
`65
`
`2
`signals can provide estimates of location by measuring the
`phases of the subcarrier signals. Kelley et al. in US. Pat. No.
`5,173,710 disclose a system that allows determination of a
`location of a vehicle. FM subcarrier signals are received
`from three FM radio stations with known locations but
`unknown relative phases by signal processors at the vehicle
`as well as at a fixed station having a known location. The
`fixed station processor determines the relative phase of the
`signals transmitted by the three FM radio stations and
`transmits the relative phase information to the vehicle. The
`vehicle processor determines its location from the FM
`subcarrier signal phases and from the relative phase infor-
`mation it receives. A limitation of cellular systems and FM
`subcarrier systems for location determination is that they are
`limited to small regions, with diameters of the order of
`20—50 km.
`
`Satellite-based location determination systems such as
`GPS and GLONASS, use the intersection of spherical sur-
`face areas to provide location information with a typical
`(selective availability) accuracy of 100 meters, anywhere on
`or near the surface of the earth. These systems may also be
`used to obtain positional accuracies within 1 centimeter. The
`satellite-based location determination systems include sat-
`ellites having signal transmitters to broadcast location infor-
`mation and control stations on earth to track and control the
`satellites. Location determination receivers process the sig-
`nals transmitted from the satellites and provide location
`information to the user.
`
`The Global Positioning System (GPS) is part of a satellite
`navigation system developed by the United States Defense
`Department under its NAVSTAR satellite program. A fully
`operational GPS includes up to 24 satellites approximately
`uniformly dispersed around six circular orbits with four
`satellites each, the orbits being inclined at an angle of 55°,
`relative to the equator, and being separated from each other
`by multiples of 60° longitude. The orbits have radii of
`26,560 kilometers and are approximately circular. The orbits
`are non-geosynchronous, with 0.5 sidereal day (11.967
`hours) orbital time intervals, so that the satellites move with
`time, relative to the Earth below. Theoretically, four or more
`GPS satellites will have line of sight to most points on the
`Earth’s surface, and line of sight access to three or more such
`satellites can be used to determine an observer‘s position
`anywhere on the Earth’s surface, 24 hours per day. Each
`satellite carries a cesium or rubidium atomic clock to
`provide timing information for the signals transmitted by the
`satellites. Internal clock correction is provided for each
`satellite clock.
`
`A second configuration for global positioning is
`GLONASS, placed in orbit by the former Soviet Union and
`now maintained by the Russian Republic. GLONASS also
`uses 24 satellites, distributed approximately uniformly in
`three orbital planes of eight satellites each. Each orbital
`plane has a nominal inclination of 648° relative to the
`equator, and the three orbital planes are separated from each
`other by multiples of 120° longitude. The GLONASS cir—
`cular orbits have smaller radii, about 25,510 kilometers, and
`a satellite period of revolution of 8/17 of a sidereal day (11.26
`hours). A GLONASS satellite and a GPS satellite will thus
`complete 17 and 16 revolutions, respectively, around the
`Earth every 8 sidereal days. The signal frequencies of both
`GPS and GLONASS are in L-band (1 to 2 GHz).
`Because the signals from the satellites pass through the
`troposphere for only a short distance,
`the accuracy of
`satellite location determination systems such as GPS or
`GLONASS is largely unalfected by weather or local anoma-
`lies. A limitation of GLONASS is that it is not clear that the
`
`K-40 Electronics, LLC Exhibit 1002, page 5
`
`K-40 Electronics, LLC Exhibit 1002, page 5
`
`

`

`US 6,252,544 B1
`
`
`
`3
`Russian Republic has the resources to complete and to
`maintain the system for full world wide 24 hour coverage.
`The inherent accuracy of the GPS position measured by a
`commercial GPS receiver is approximately 20 meters.
`However, the United States Government currently intention—
`ally degrades the accuracy of GPS computed positions for
`commercial users with Selective Availability, SA. With SA,
`the GPS position accuracy of a commercial GPS receiver is
`approximately 100 meters. However, higher accuracy is
`available with the use of secret decryption codes.
`Differential Global Positioning System, DGPS, is a tech—
`nique for enhancing the accuracy of the GPS position, and
`of course may be applied to GLONASS as well. The DGPS
`comprises the Global Positioning System together with a
`GPS reference station receiver situated at a known position.
`DGPS error correction information is derived by taking the
`difference between the measurements made by the GPS
`reference station and the expected measurement at
`the
`(nown position of the reference station. DGPS error cor-
`rection information can be in the form of GPS satellite
`aseudorange olfsets or GPS position offsets. If GPS position
`offsets are used, the GPS satellites used in the calculation of
`he GPS position must be included as part of the DGPS error
`correction information. Aprocessor in a “differential-ready"’
`GPS receiver applies the DGPS error correction information
`o enhance the GPS position to an accuracy in the range of
`10 meters to a less than one meter.
`
`Two types of DGPS exist, postprocessed and realtime. In
`aostprocessed systems, the DGPS error correction informa-
`ion and a user’s GPS position information are processed
`after the user has completed his data acquisition. In realtime
`systems, the DGPS error correction information is transmit-
`ed to the GPS user in a DGPS telemetry stream, e.g., a radio
`wave signal, and processed by a differential-ready GPS
`receiver as the application progresses. Realtime processing
`is desirable for many applications because the enhanced
`accuracy of DGPS is available to the GPS user while in the
`field. Realtime broadcast of DGPS error correction infor—
`mation is available from many sources, both public and
`private, including Coast Guard RDF beacon and commer—
`cially operated FM broadcast subcarriers. A DGPS radio
`wave receiver is required to receive the DGPS radio wave
`signal containing the DGPS error correction information,
`and pass the DGPS error corrections to the differential—ready
`GPS receiver.
`
`Many applications of GPS including mineral surveying,
`mapping, adding attributes or features to maps, finding sites
`on a map, vehicle navigation, airplane navigation, marine
`navigation, field asset management, geographical informa-
`tion systems, and others require the enhanced accuracy that
`is available with DGPS. For instance, a 20 to 100 meter error
`could lead to unintentional trespassing, make the return to an
`underground asset difficult, or put a user on the wrong block
`while walking or driving in a city. These applications require
`a computer to store and process data, retain databases,
`perform calculations, display information to a user, and take
`input from a user entry. For instance, the user may need to
`store a map database, display a map, add attributes to
`features on the map, and store these attributes for geographi-
`cal information. The user may also need to store and display
`locations or calculate range and bearing to another location.
`GPS is typically used by many professionals engaged in
`navigation and surveying fields such as marine navigation,
`aircraft piloting, seismology, boundary surveying, and other
`applications where accurate location is required or where the
`cost of GPS is small compared to the cost of a mistake in
`
`4
`determining location. Some mobile professionals in the
`utilities,
`insurance,
`ranching, prospecting, ambulance
`driving, trucking, delivery, police, fire, real estate, forestry,
`and other mobile applications use GPS to save time in their
`work. GPS is also used for personal travel such as hiking,
`biking, horseback riding, yachting, fishing, driving in per—
`sonal cars, and other travel activities. To enhance the use-
`fulness of GPS a number of sources have integrated maps
`into the output, or provide a global information system (GIS)
`to process the GPS output. Thus, it is known to sort and
`display proximate map features and/or attributes in the same
`coordinate system as the position information.
`As disclosed in US. Pat. No. 5,528,248, incorporated
`herein by reference, a satellite location determination system
`using Global Positioning System (GPS) satellite signal
`transmitters receives a spread spectrum L1 carrier signal
`having a frequency=1575.42 MHZ. The L1 signal from each
`satellite signal transmitter is binary phase shift key (BPSK)
`modulated by a Coarse/Acquisition (C/A) pseudo—random
`noise (PRN) code having a clock or chip rate of f0=1.023
`MHZ. Location information is transmitted at a rate of 50
`baud. The PRN codes allow use of a plurality of GPS
`satellite signal transmitters for determining an observer’s
`position and for providing location information. A signal
`transmitted by a particular GPS satellite is selected by
`generating and correlating the PRN code for that particular
`satellite signal transmitter with a GPS signal received from
`that satellite. All C/A PRN codes used for GPS satellite
`signals are known and are stored and/or generated in a GPS
`receiver. A bit stream from the GPS satellite signal trans—
`mitter includes an ephemeris location of the GPS satellite
`signal transmitter, an almanac location for all GPS satellites,
`and correction parameters for ionospheric signal propaga-
`tion delay, and clock time of the GPS satellite signal
`transmitter. Accepted methods for generating the C/A-code
`are set forth in the document GPS Interface Control Docu-
`ment ICD-GPS-200, published by Rockwell International
`Corporation, Satellite Systems Division, Revision A, Sep.
`26, 1984, which is incorporated by reference herein.
`Energy on a single carrier frequency from all of the
`. satellites is transduced by the receiver at a point close to
`Earth. The satellites from which the energy originated are
`identified by modulating the carrier transmitted from each
`satellite with pseudorandom type signals.
`In one mode,
`referred to as the coarse/acquisition (C/A) mode, the pseu-
`dorandom signal is a gold code sequence having a chip rate
`of 1.023 MHz;
`there are 1,023 chips in each gold code
`sequence, such that the sequence is repeated once every
`millisecond (the chipping rate of a pseudorandom sequence
`is the rate at which the individual pulses in the sequence are
`derived and therefore is equal to the code repetition rate
`divided by the number of members in the code; one pulse of
`the noise code is referred to as a chip).
`The 1.023 MHZ gold code sequence chip rate enables the
`position of the receiver responsive to the signals transmitted
`from four of the satellites to be determined to an accuracy of
`approximately 60 to 300 meters.
`There is a second mode, referred to as the precise or
`protected (P) mode, wherein pseudorandom codes with chip
`rates of 10.23 MHZ are transmitted with sequences that are
`extremely long, so that the sequences repeat no more than
`once per week. In the P mode, the position of the receiver
`can be determined to an accuracy of approximately 16 to 30
`meters. However, the P mode requires Government classi—
`fied information about how the receiver is programmed and
`is intended for use only by authorized receivers. Hence,
`civilian and/or military receivers that are apt to be obtained
`by unauthorized users are not responsive to the P mode.
`
`10
`
`15
`
`60
`
`65
`
`K-40 Electronics, LLC Exhibit 1002, page 6
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`K-40 Electronics, LLC Exhibit 1002, page 6
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`

`

`US 6,252,544 B1
`
`5
`To enable the receivers to separate the C/A signals
`received from the dilferent satellites, the receiver includes a
`plurality of different locally derived gold code sources, each
`of which corresponds with the gold code sequence trans-
`mitted from one of the satellites in the field of the receiver
`The locally derived and the transmitted gold code sequences
`are cross correlated with each other over one millisecond,
`gold code sequence intervals. The phase of the locally
`derived gold code sequences vary on a chip-by-chip basis,
`and then within a chip, until the maximum cross correlation
`function is obtained. Since the cross correlation for two gold
`code sequences having a length of 1,023 bits is approxi—
`mately 16 times as great as the cross correlation function of
`any of the other combinations of gold code sequences, it is
`relatively easy to lock the locally derived gold code
`sequence onto the same gold code sequence that was trans—
`mitted by one of the satellites.
`The gold code sequences from at least four of the satellites
`in the field of View of the receiver are separated in this
`manner by using a single channel that is sequentially respon—
`sive to each of the locally derived gold code sequences or by
`using parallel channels that are simultaneously responsive to
`the different gold code sequences. After four locally derived
`gold code sequences are locked in phase with the gold code
`sequences received from four satellites in the field of view
`of the receiver, the position of the receiver can be deter—
`mined to an accuracy of approximately 60 to 300 meters.
`The approximately 60 to 300 meter accuracy of GPS is
`determined by (1) the number of satellites transmitting
`signals to which the receiver is effectively responsive, (2)
`the variable amplitudes of the received signals, and (3) the
`magnitude of the cross correlation peaks between the
`received signals from the different satellites.
`In response to reception of multiple pseudorange noise
`(PRN) signals, there is a common time interval for some of
`the codes to likely cause a degradation in time of arrival
`measurements of each received PRN due to the cross
`correlations between the received signals. The time of
`arrival measurement for each PRN is made by determining
`the time of a peak amplitude of the cross correlation between
`the received composite signal and a local gold code
`sequence that is identical to one of the transmitted PRN.
`When random noise is superimposed on a received PRN,
`increasing the averaging time of the cross correlation
`between the signal and a local PRN sequence decreases the
`average noise contribution to the time of arrival error.
`However, because the cross correlation errors between the
`received PRN’s are periodic, increasing the averaging time
`increases both signal and the cross correlation value between
`the received PRN’s alike and time of arrival errors are not
`reduced.
`
`The GPS receiver may incorporate a Kalman filter, which
`is adaptive and therefore automatically modifies its thresh-
`old of acceptable data perturbations, depending on the
`velocity of the vehicle (GPS antenna). This optimizes sys-
`tem response and accuracy of the GPS system. Generally,
`when the vehicle increases velocity by a specified amount,
`the GPS Kalman filter will raise its acceptable noise thresh-
`old. Similarly, when the vehicle decreases its velocity by a
`specified amount,
`the GPS Kalman filter will
`lower its
`acceptable noise threshold.
`Extremely accurate GPS receivers depend on phase mea—
`surements of the radio carriers that they receive from various
`orbiting GPS satellites. Less accurate GPS receivers simply
`develop the pseudoranges to each visible satellite based on
`the time codes being sent. Within the granularity of a single
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`15
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`time code, the carrier phase can be measured and used to
`compute range distance as a multiple of the fundamental
`carrier wavelength. GPS signal transmissions are on two
`synchronous, but separate, carrier frequencies “L1” and
`“L2”, with wavelengths of nineteen and twenty-four
`centimeters, respectively. Thus within nineteen or twenty—
`four centimeters, the phase of the GPS carrier signal will
`change 360° (23': radians). However, the number of whole
`cycle (360°) carrier phase shifts between a particular GPS
`satellite and the GPS receiver must be resolved. At
`the
`receiver, every cycle will appear essentially the same, over
`a short time frame. Therefore there is an “integer ambiguity”
`in the calculation. The resolution of this integer ambiguity is
`therefore a calculation-intensive arithmetic problem to be
`solved by GPS receivers. The traditional approaches to such
`integer ambiguity resolution have prevented on-the-fly solu-
`tion measurement updates for moving GPS receivers with
`centimeter accurate outputs. Very often, such highly accu-
`rate GPS receivers have required long periods of motion-
`lessness to produce a first and subsequent position fix.
`There are numerous prior art methods for resolving inte-
`ger ambiguities. These include integer searches, multiple
`antennas, multiple GPS observables, motion-based
`approaches, and external aiding. Search techniques often
`require significant computation time and are vulnerable to
`erroneous solutions or when only a few satellites are Visible.
`More antennas can improve reliability considerably. If car—
`ried to an extreme, a phased array of antennas results,
`whereby the integers are completely unambiguous and
`searching is unnecessary. But for economy, reduced size,
`complexity and power consumption, the minimum number
`of antennas required to quickly and unambiguously resolve
`the integers, even in the presence of noise, is preferred.
`One method for integer resolution is to make use of the
`other observables that modulate a GPS timer, The pseudo-
`random code imposed on the GPS satellite transmission can
`be used as a coarse indicator of differential range, although
`it is very susceptible to multipath problems. Differentiating
`the L1 and L2 carriers in phase sensitive manner provides a
`longer effective wavelength, and reduces the search space,
`i.e., an ambiguity distance increased from 19 or 24 centi-
`meters to about 456 centimeters. However, dual frequency
`receivers are expensive because they are more complicated.
`Motion-based integer resolution methods make use of addi-
`tional information provided by platform or satellite motion.
`But such motion may not always be present when it is
`needed. Another prior art technique for precision attitude
`determination and kinematic positioning is described by
`Hatch, in U.S. Pat. No. 4,963,889, incorporated herein by
`reference, which employs two spaced antennas, moveable
`with respect to each other. Knight, U.S. Pat. No. 5,296,861,
`incorporated herein by reference, provides a method of
`reducing the mathematical intensity of integer ambiguity
`resolution. See also, U.S. Pat. No. 5,471,218, incorporated
`herein by reference.
`Direct range measurements, combined with the satellite
`geometry, may also allow the correct integer carrier phase
`ambiguities to be determined for a plurality of satellites
`tracked at two or more sites. The use of additional sensors,
`such as a laser level, electronic distance meter, a compass,
`a tape, etc., provide valuable constraints that
`limit
`the
`number of possible integer ambiguities that need to be
`considered in a search for the correct set.
`
`Many systems using handheld computers, having soft-
`ware and databases defining maps and running standard
`operating systems, have been coupled to GPS Smart Anten-
`nas. Wireless, infrared, serial, parallel, and PCMCIA inter-
`
`K-40 Electronics, LLC Exhibit 1002, page 7
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`K-40 Electronics, LLC Exhibit 1002, page 7
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`US 6,252,544 B1
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`7
`faces have been used to interconnect the handheld computer
`and the GPS Smart Antenna. Differential-ready GPS Smart
`Antennas having an input to receive signals representative of
`DGPS error corrections are also commercially available.
`Further, GPS receivers and Differential-ready GPS Smart
`Antennas which are self contained, built onto a type II
`PCMCIA card (PC Card), and/or having serial data com-
`munications ports (RS-232 or RS-422) are commercially
`available. See, U.S. Pat. No. 5,276,451, and U.S. Pat. No.
`5,210,540, assigned to Pioneer Electronic Corporation.
`There are several different types of vehicle navigational
`systems. The first system makes use of stored map displays
`wherein the maps of a predetermined area are stored in the
`in—Vehicle computer and displayed to the vehicle operator or
`driver. The maps, combined with information describing the
`location where the vehicle started and where it is to go, will
`highlight the direction and the driver will have to read the
`display and follow the route. One such stored map display
`system was offered by General Motors on their 1994
`Oldsmobile, using Global Positioning System (GPS) satel-
`lites and dead reckoning techniques, and likely map match-
`ing to determine a precise location. The vehicle has radio
`receivers for receiving data from satellites, giving the loca-
`tion of the receiver expressed in latitude and longitude. The
`driver enters details of the desired destination into an
`on-board or in-Vehicle computer in the form of specific
`address, a road intersection, etc. The stored map is
`displayed, allowing the operator to pinpoint
`the desired
`destination. The on—board computer then seeks to calculate
`the most efficient route, displaying the distance to, and the
`direction of, each turn using graphics and a voice prompt.
`Other known systems employ speech recognition as a user
`input. For example, another system, described in U.S. Pat.
`No. 5,274,560 does not use GPS and has no sensing devices
`connected to the vehicle. The routing information is con-
`tained in a device that is coupled to a CD player in the
`vehicle’s audio system. Commands are entered into the
`system Via a microphone and the results are outputted
`through the vehicle’s speakers. The vehicle operator spells
`out the locations and destinations, letter by letter. The system
`confirms the locations by repeating whole words. Once the
`system has received the current location and destination, the
`system develops the route and calculates the estimated time.
`The operator utilizes several specific performance
`commands, such as “Next”, and the system then begins to
`give segment by segment route directions.
`Still another system, such as the Siemens Ali-ScoutTM
`system,
`requires that
`the driver key-in the destination
`address coordinates into the in-vehicle computer. A compass
`located in the vehicle then gives a “compass” direction to the
`destination address. Such a compass direction is shown in
`graphics as an arrow on a display unit,
`indicating the
`direction the driver should go. Along the side of the road are
`several infrared beacon sites which transmit data informa—
`tion to a properly equipped vehicle relative to the next
`adjacent beacon site. From all of the information received,
`the iii-vehicle computer selects the desired beacon data
`information to the next beacon and displays a graphic
`symbol for the vehicle operator to follow and the distance to
`the desired destination. In this system, there is no map to
`read; both a simple graphic symbol and a segment of the
`route is displayed, and a voice prompt telling the vehicle
`operator when to turn and when to continue in the same
`direction is enunciated. Once the program begins, there is
`minimal operator feedback required.
`U.S. Pat. No. 4,350,970, describes a method for traffic
`management in a routing and information system for motor
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`8
`vehicle traffic. The system has a network of stationary
`routing stations each located in the vicinity of the roadway,
`which transmit route information and local
`information
`concerning its position to passing vehicles. The trip desti-
`nation address is loaded by the vehicle o