GPS RECEIVER SYSTEM
`LINKED BY INFRARED SIGNALS
`
`Primary Examiner-Gregory
`
`Attorney, Agent,
`
`Dec. 31, 1996
`
`I
`1111111111111111 11111 lllll 111111111111111 111111111111111 lll111111111111111
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`US005589835A
`[lll Patent Number:
`5,589,835
`
`United States Patent
`r191
`[45]Date of Patent:
`Gildea et al.
`
`C. Issing
`
`or Firm-David R. Gildea
`
`[54]DIFFERENTIAL
`Menlo Park; Lloyd
`[75]Inventors:
`[57]
`Palo Alto, both of Calif.
`A GPS receiver system to determine and display a geo­
`
`
`
`
`
`
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`graphical differential Global Positioning System (DGPS)
`[73]Assignee:
`
`
`
`location where the components of the system are intercon­
`
`Sunnyvale, Calif.
`
`
`nected with. an airwave infrared (IR) link. The system
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`
`
`includes a GPS Smart Antenna receiver module to determine
`[21]Appl. No.: 359,604
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`
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`the geographical location of the module, a DGPS radio
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`
`
`
`receiver to receive an airwave radio frequency DGPS signal
`[22]Filed:Dec. 20, 1994
`
`
`
`
`having DGPS correction information, and a personal com­
`[51]Int. Cl.6 ..........................
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`
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`puting display to run an application program and to display
`.............................. G0lS 5/02
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`
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`the geographical DGPS location and application information
`
`[52]U.S. Cl ............................................................... 342/357
`342/357
`[58]Field of Search
`
`
`that is useful to a user. The GPS Smart Antenna receiver
`...............................................
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`
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`module and the DGPS radio receiver are switched on and off
`
`
`
`
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`from the personal computing display through the airwave IR
`link.
`U.S. PATENT DOCUMENTS
`
`
`
`9/1994 Gildea et al ............................ 342/357
`5,345,244
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`5,361,212 11/1994 Class et al .............................. 342/357
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`
`
`David R. Gildea,
`H. Banta,
`
`ABSTRACT
`
`
`
`Trimble Navigation Limited,
`
`
`
`[56]
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`
`
`References Cited
`
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`
`15 Claims, 2 Drawing Sheets
`
`-----
`
`DGPS radio
`
`receiver 50
`tuner radio
`airwave
`52 battery 59
`
`
`radio frequency
`OGPS signal
`power m radio
`t. t
`power out--power
`power in supply
`60
`GPS signal
`DGPS IR
`DGPS IR
`from GPS satellites
`transmitter
`receiver
`54
`56
`I
`, I�.\,
`GPS antenna
`I14
`/ \_IR DGPS
`
`signal 55
`
`power in--- module IR
`'/
`display ___ W- micro-
`1--------1---i lransmitter
`GPS engine15 I
`IR receiver
`circuit --'"- processor
`
`16
`20 Ir 43
`36
`out L _ module
`")
`t . power
`IR module \
`IR
`power In module,_ __ receiver
`t
`
`17 .:::,....._,.----. __IR control signal /
`display i-- LJ -
`.-----�-----,
`JR transmitter
`
`module L- power
`18
`22
`
`code 38 variable executable
`.__b_at_te--"ry_..:.57'--''I
`
`signal 23 )
`· supply 58
`data 40
`GPS Smart Antenna
`
`infrared (IR) link 26
`memory 42
`
`
`receiver module 12
`
`processor system 32
`
`GPS receiver system 10
`
`
`personal computing display 13
`
`visual or audible
`
`display to user
`entry from user
`
`display
`user
`device
`entry
`device
`44
`46
`
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`IPR2020-00409
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`visual or audible
`
`
`display to user
`entry from user
`
`DGPS radio
`50
`receiver
`tuner radio
`airwave
`52 battery
`radio frequency
`59
`UGPS signal t. t
`power in
`radio
`power out---
`power
`supply 60
`powe�in
`GPS signal
`DGPS IR
`t DGPS JR
`from GPS satellites
`receiver
`transmitter
`54
`56
`I GPS anten�� I
`I -ii.\--
`\_ JR DGPS
`signal
`55 .
`t-- module IR �
`power in-
`display
`micro-
`ga �
`
`transmitter � t----
`I GPS engine 1151
`JR receiver
`circuit processor
`16 � /
`�
`43
`36
`f power out
`module JR J� module
`power in t module .-
`' .
`receiver signal
`17
`,:;,__ � display
`�
`,,.,---. --
`JR transmitter
`18
`IR control
`I module ,r--power
`/_
`executable
`22
`
`signal 23 )
`battery 57 supply 58
`code 38 data 40
`GPS Smart Antenna
`memory 42
`infrared (IR) link 26
`
`
`receiver module 12
`
`processor system 32
`personal computing display 13
`
`
`�
`
`J/0
`
`�
`
`,-
`
`FIG. 1
`
`
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`""""
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`0
`....,
`N
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`variable
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`u-.
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`u-. 00
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`-. 00
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`u-.
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`user display
`entry device
`
`device 44
`46
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`
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`U.S. Patent
`Dec. 31, 1996
`
`Sheet 2 of 2
`
`5,589,835
`
`start
`
`start
`
`user enters "on"
`command
`
`80
`
`user enters "off"
`
`command
`
`90
`
`add ID to "on"
`command
`
`81
`
`add ID to "off"
`command
`
`91
`
`issue electronic
`
`signal to IR transmitter
`82
`
`issue electronic
`
`signal to IR transmitter
`92
`
`broadcast IR
`
`signal
`
`83
`
`broadcast IR
`
`signal
`
`93
`
`
`
`receive IR signal
`
`
`
`receive IR signal
`
`84
`
`94
`
`recognize ID and
`
`
`control information
`86
`
`recognize ID and
`
`
`control information
`96
`
`operating power
`
`
`switched on
`
`87
`
`operating power
`
`switched off
`
`97
`
`stop
`
`stop
`
`FIG. 2a
`
`FIG. 2b
`
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`CROSS REFERENCE OF RELATED
`APPLICATIONS
`
`
`
`BACKGROUND OF THE INVENTION
`
`5,589,835
`
`1
`
`DIFFERENTIAL GPS RECEIVER SYSTEM
`
`
`LINKED BY INFRARED SIGNALS
`
`2
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`depending upon which of the various airwave signals the
`
`DGPS radio receiver is to receive.
`Another important figure of merit for a GPS receiver is
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`portable computing power. In many applications, the GPS
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`5 location or the DGPS location is processed to provide
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`further information that is useful to a user. For example, a
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`geographic information system (GIS) application may store
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`This application is related to a continuation in part appli­
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`the geographical locations and attributes of map features in
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`cation of David R. Gildea et al., Ser. No. 08/225125, filed
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`
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`the form of an electronic map. A navigation application may
`
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`Apr. 6, 1994, to its parent application Ser. No. 07/978274,
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`10 need to compute a distance and a direction to a selected map
`
`filed Nov. 18, 1992, to an application of David R. Gildea,
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`feature or to a map feature having a selected set of the
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`Ser. No. 08/157609, filed Nov. 23, 1993, and to an applica­
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`attributes. Such applications require a large memory and are
`
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`tion of Glenn C. Steiner et al., Ser. No. 08/293048 filed Aug.
`
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`most expediently programmed in a processing system that
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`19, 1994. All of these applications are assigned to the
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`has the power to run a standard operating system, such as
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`assignee of the present application.
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`15 DOS, DOS with Windows, Macintosh, GeoWorks, and
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`others. Fortunately, personal computing devices have
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`recently become available that have the portability, memory,
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`and processing power to run these applications.
`1.Field of the Invention
`
`
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`Several formats of GPS receiver systems exist or have
`20
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`The invention relates generally to Global Positioning
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`been proposed that include system components of the GPS
`
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`System (GPS) receivers and more particularly to a GPS
`
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`receiver, the DGPS radio receiver, and the personal com­
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`
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`receiver system wherein a GPS Smart Antenna, a differential
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`puting device in order to provide DGPS location capability,
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`GPS radio receiver, and a personal computing device are
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`portability, and processing power. In a first format, the
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`coupled by an infrared link.
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`system components are integrated into a single unit. Such
`25
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`units may be "hardwired" into a single unit, or the GPS
`
`2.Description of the Prior An
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`receiver and the DGPS radio receiver may be housed on
`GPS receivers are now used for many applications to
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`Personal Computer Memory Card Interface Association
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`provide a geographical location. The GPS receiver includes
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`(PCMCIA) cards that plug into the personal computing
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`a GPS antenna to receive a GPS signal transmitted from one
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`device to give the effect of a single unit. An advantage of
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`or more GPS satellites, a GPS engine to compute the
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`30 using PCMCIA cards, is that the various constructions of
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`geographical location of the antenna and the time of obser­
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`DGPS radio receivers do not prevent the manufacture of a
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`vation of that location, a display processor to convert the
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`standard construction of the GPS receiver on a separate card.
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`location and observation time into information that is useful
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`A problem with this format is that the user must remain in
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`for an application, and a display device to show the infor­
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`the open to preserve a direct line of sight from the GPS
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`mation to the user. The antenna must be positioned with a
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`35 antenna to one or more GPS satellites while operating and
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`line of sight to the satellite or satellites from which the
`direct
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`observing the personal computing device. One solution to
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`signals are received.
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`this problem is to place the GPS antenna in a separate unit,
`is accuracy An important figure of merit in a GPS receiver
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`connected with the GPS receiver system by a cable. In a
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`of the geographical location. The inherent accuracy of the
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`second format, the system components are each housed in
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`GPS location measured by a commercial GPS receiver is
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`40 separate units and interconnected with cables. This format
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`approximately 20 meters. However, the United States Gov­
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`retains the advantages of separating the GPS antenna from
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`ernment currently employs selective availability (SA) to
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`the system and of having a standardized construction of the
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`degrade the accuracy of the GPS location that is determined
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`GPS receiver. However, cables and their connections are
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`by a commercial GPS receiver. With SA the GPS location
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`expensive, prone to breakage or malfunction, and inconve-
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`accuracy is approximately 100 meters. Several applications
`45 nient for some applications.
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`require a geographical location accuracy that is better than
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`In a third format, the GPS receiver and the DGPS radio
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`100 meters or even 20 meters. For example, a 100 to 20
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`receiver components are integrated into a GPS/DGPS Smart
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`meter location error could lead to unintentional trespassing,
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`Antenna unit. The GPS/DGPS Smart Antenna unit may use
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`make the return to an underground marker or mineral
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`link toor infrared (IR) frequency 50 a wireless radio frequency
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`difficult, place a motor vehicle on the wrong block, or cause
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`connect to the personal computing device. The IR frequency
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`a navigator to choose an incorrect course for a boat or an
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`link has the advantage that it does not interfere with recep­
`airplane.
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`tion of airwave radio frequency signals used for navigation
`GPS
`Fortunately, both the inherent and the SA-degraded
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`and does not require testing or certification by the FAA or
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`location accuracy can be improved by the application of
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`prob­55 FCC. This format eliminates the expense, reliability
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`differential GPS (DGPS) corrections. In general, the DGPS
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`lems, and inconvenience of the cable but, does not allow a
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`corrections are derived by taking the difference between a
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`standard construction of the GPS receiver component.
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`GPS location determined by a GPS receiver located at a
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`There is a need for a GPS receiver system to provide a
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`reference site and a surveyed location of the reference site.
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`geographical DGPS location, where the system includes a
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`Various airwave radio frequency signals are now available
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`and where the construction 60 GPS receiver having a standard
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`from a variety of sources to provide the DGPS corrections
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`system components are interconnected by an infrared (IR)
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`in real time to a mobile GPS receiver system. A DGPS radio
`link.
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`receiver included as a part of a GPS receiver system receives
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`the airwave signal carrying the DGPS corrections. The
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`SUMMARY OF THE INVENTION
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`mobile GPS receiver system uses the DGPS corrections to
`It is therefore an object of the present invention to provide
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`correct the GPS location. The corrected GPS location,
`65
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`a GPS receiver system to determine and display a geographi­
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`termed a "DGPS location" has an accuracy in a range of 10
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`cal DGPS location where the system includes a GPS Smart
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`constructions for the DGPS radio receiver are required
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`3
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`5,589,835
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`4
`antenna 14 to receive an airwave GPS signal, having infor­
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`Antenna receiver module, a DGPS radio receiver, and a
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`mation for the determination of a GPS location, from a
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`personal computing display in separate packages each com­
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`plurality of GPS satellites and to issue a responsive elec­
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`municating with the others without cables by using an
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`tronic antenna output signal to a GPS engine 15. The GPS
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`airwave infrared (IR) link.
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`15 computes the geographic location from the infor­
`5 engine
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`Another object is to provide internal batteries to supply
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`mation in the GPS signal and issues data indicative of the
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`operating power within the GPS Smart Antenna receiver
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`location in an electronic signal to a module infrared (IR)
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`module and within the DGPS radio receiver and to control
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`transmitter 16. Several GPS antennas 14 and the GPS
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`the supply of operating power within the module and within
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`engines 15 that are suitable for the construction of the
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`the radio from the personal computing display through the
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`available, such as a10 present invention are commercially
`IR link.
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`that model "SV6" manufactured by Trimble Navigation
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`Briefly, the preferred embodiment includes the GPS
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`includes both the GPS antenna 14 and the GPS engine 15,
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`Smart Antenna receiver module to determine the geographi-
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`a model "NavCore Microtracker" manufactured by Rock­
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`cal location of the module, the DGPS radio receiver to
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`well that includes the GPS engine 15, and a variety of
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`receive an airwave radio frequency DGPS signal having
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`models manufactured by MicroPulse located in Camarillo,
`15
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`DGPS correction information, and the personal computing
`
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`14.
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`Calif. that include the GPS antenna
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`display to run an application program and to display the
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`The module IR transmitter 16 transmits an IR module
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`geographical DGPS location and application information
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`signal 17, including the location data, by illuminating a cone
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`that is useful to a user. The GPS Smart Antenna module, the
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`of local airspace emerging from the module IR transmitter
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`DGPS radio receiver, and the personal computing display
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`16 with energy in the IR wavelength range. The module 12
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`communicate information through the airwave IR link. 20
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`includes a module IR receiver 18 to receive IR signals
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`An advantage of the present invention is that the GPS
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`having information to control the operation of the module
`Smart Antenna receiver module, the DGPS radio receivers,
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`12.The personal computing display 13 includes a display IR
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`and the personal computing display are packaged separately,
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`receiver 20 to receive IR signals in the local airspace
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`thereby allowing various constructions of DGPS radio
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`17 and a display IR trans­
`25 including the IR module signal
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`receivers while retaining standardization of the construction
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`mitter 22 to transmit an IR control signal 23 by illuminating
`of the GPS receiver.
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`a cone of local airspace with IR energy. The module IR
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`transmitter 16 and the display IR transmitter 22 may be
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`Another advantage is that the GPS receiver, the DGPS
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`constructed from a light emitting diode (LED), such as a
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`radio receiver, and the personal computing display commu­
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`nicate via a cableless IR link, thereby eliminating the cost,
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`manufactured by Tele­30 "TSUS5402" or a ''TSHA5503"
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`funken Semiconductors driven by a transistor, using appli­
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`failure potential, and inconvenience of cable connections.
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`cation information available from Telefunken. The use of
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`Another advantage is that the lifetimes of the internal
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`multiple LEDs in the module IR transmitter 16 and/or the
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`batteries in the GPS Smart Antenna receiver module and in
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`display IR transmitter 22 can be used to widen the cone of
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`the DGPS radio receiver may be prolonged by controlling
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`23,17 and/or signal
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`35 the IR module signal the IR control
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`the supply of operating power within the module and within
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`20 respectively IR receiver 18 and the display IR receiver
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`the radio receiver from the personal computing display
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`may be constructed from a photodiode, such as a "BPV23F'
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`through the IR link.
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`or a BPV23NF' manufactured by Telefunken Semiconduc­
`These and other objects and advantages of the present
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`tors, and an "SIRComm2" integrated circuit IR receiver
`
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`invention will no doubt become obvious to those of ordinary
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`informa­40 manufactured by Irvine Sensors using application
`skill in the art after having read the following detailed
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`tion available from Telefunken or Irvine. Alternatively, a
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`description of the preferred embodiments which are illus­
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`model "CS8130 Multi-Standard Infrared Transceiver"
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`trated in the various figures.
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`manufactured by Crystal Semiconductors can be used with
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`the above-identified LED and photodiode for both the mod-
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`16 and the module IR receiver 18 and/or
`45 ule IR transmitter
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`for both the display IR transmitter 22 and the display
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`IR
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`FIG. 1 is a block diagram of a GPS receiver system
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`receiver 20. Another source of parts is Hewlett-Packard
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`providing a geographical differential GPS location;
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`which provides licenses to use its serial infrared communi­
`FIG. 2a is a flow chart of the steps to turn on the operating
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`
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`disclosed in U.S. Pat. cations interface (SIR) transceivers
`
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`power in a GPS Smart Antenna receiver module and in a
`
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`50 No. 5,075,792, the teachings of which are incorporated
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`DGPS radio receiver that are a part of the system of FIG. 1;
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`herein by reference. The module IR transmitter 16, the
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`and
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`module IR receiver 18, the display IR receiver 20, the
`FIG. 2b is a flow chart of the steps to turn off the operating
`
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`display IR transmitter 22, the IR module signal 17, and the
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`
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`power in the GPS Smart Antenna receiver module and in the
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`IR control signal 23 are included in an IR link 26 to
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`DGPS radio receiver of FIG. 2a.
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`of the sys­components 55 communicate information between
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`receiver module tem 10 including the GPS Smart Antenna
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`13. 12 and the personal computing display
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`The personal computing display 13 includes a processor
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`system 32 for receiving, processing, and issuing electronic
`of the present FIG. 1 illustrates a GPS receiver system
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`32 includes a microprocessor
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`invention and referred to by the general reference number
`60 signals. The processor system
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`36 that operates in a conventional manner to receive elec­
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`receivera GPS Smart Antenna 10.The system 10 includes
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`module 12 to determine a geographical location of the
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`tronic signals and to process the signals according to pre­
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`module 12 and a personal computing display 13 to display
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`programmed instructions in an executable code 38 and
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`the location to a human user. The module 12 is housed in a
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`43, variable data 40 stored in a memory 42. An 1/0 circuit
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`single waterproof package, no more than 15 centimeters
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`Receiver 65 such as a Universal Asynchronous/synchronous
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`high and no more than 15 centimeters wide in any dimension
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`Transmitter (UART), available as an electronic part from
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`perpendicular to the height. The module 12 includes a GPS
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`many vendors, converts parallel data electronic signals from
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`DETAILED DESCRIPTION OF THE
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`PREFERRED EMBODIMENTS
`
`IN THE DRAWINGS
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`IPR2020-00409
`Apple EX1020 Page 5
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`5,589,835
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`5
`6
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`the microprocessor 36 to serial data electronic signals to the
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`version 2, RTCM
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`for Differential NavStar GPS Service,
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`display IR receiver 20 and converts serial data electronic
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`Special Committee No. 104, Jan. 1, 1990, published by the
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`signals from the display IR receiver 20 to parallel data
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`RTCM, PO Box 19087, Washington, D.C. 20036, U.S.A.
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`electronic signals to the microprocessor 36. A user entry
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`which is incorporated by reference herein. The FM subcar-
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`device 44, such as a keyboard, a keypad, a touchscreen, a
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`to commercial users throughout 5 rier signals are available
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`switch, a microphone, or a combination thereof, is operated
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`most of the industrialized world by paying a periodic fee for
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`by a human user to enter information. The user may enter
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`the key to decrypt the information. The tuner 52 is con­
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`structed for converting the FM subcarrier signal to an
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`program information, such as a selected geographical loca­
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`tion. The user entry device 44 responds by issuing a user
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`electronic DGPS correction signal including data indication
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`device electronic signal to the microprocessor 36. The
`10 of the DGPS corrections
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`is available from DCI, AccQPoint,
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`or Trimble Navigation. Another source of DGPS corrections
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`executable code 38 includes instructions to receive the
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`in an airwave radio frequency DGPS signal is the United
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`electronic signal, to store the selected geographical location
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`States Coast Guard (U.S. C. G.). The U.S. C. G. determines
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`in variable data 40 and to compute user output information
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`the DGPS corrections at certain radio direction finder (RDF)
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`of a distance and a direction between the location of the
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`beacon stations and broadcasts the corrections using the
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`36module 12 and the selected location. The microprocessor
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`15 RTCM 104 data structure without encryption as modulation
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`issues electronic display signals to a display device 46, such
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`on the RDF beacon signals transmitted from those sites.
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`as a liquid crystal (LCD), light emitting diode LED display,
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`Similar systems are in use worldwide. The RDF beacon
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`or an equivalent to display the user output information in a
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`signals are currently used for marine navigation and are
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`form that is visible to the human user. Optionally, the display
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`available to the public without charge in certain geographi-
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`device 46 includes a speaker to display the information in a
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`20 cal areas near the United States and foreign coastlines. The
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`form that is audible to the human user. In a preferred
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`tuner 52 constructed for converting the RDF beacon signal
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`embodiment, the processor system 32, the user entry device
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`to the electronic DGPS correction signal is commercially
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`44, the display device 46, the display IR receiver 20, and the
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`available from several manufacturers including Magnavox
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`display IR transmitter 22 are included in a commercially
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`and Trimble Navigation. Another source of DGPS correc-
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`available personal digital computing device, such as are
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`by John C. Chance25 tions is the OMNISTAR system provided
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`manufactured by several companies including Casio, Apple,
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`& Associates company of Houston, Tex. The OMNISTAR
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`Hewlett-Packard, and Sony and known by various names,
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`system includes the DGPS corrections in an airwave radio
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`frequency DGPS signal broadcast from geostationary satel­
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`such as a digital assistant, a personal digital assistant (PDA),
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`a personal information manager (PIM), a notebook com­
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`lites. The tuner 52 constructed to receive the OMNISTAR
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`from the John C. Chance company.30 signal is available
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`puter, a sub-notebook computer, a PCMCIA computer, a
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`Several other systems user tuners commonly called "radio/
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`"Zoomer", a "Newton," a "Dataman," or an equivalent.
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`modems" to receive airwave radio frequency DGPS signals
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`Optionally, the display IR receiver 20 and the display IR
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`transmitter 22 may be included as an accessory to the
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`in the UHF frequency range that include the DGPS correc­
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`tions. Two such systems and tuners 52 to receive the airwave
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`commercially available device.
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`inby GLB Electronics 35 UHF DGPS signals are provided
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`The GPS Smart Antenna receiver module 12 is capable of
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`Buffalo, N.Y. and Pacific Crest Corporation in Sunnyvale,
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`providing a GPS location having an accuracy of approxi­
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`Calif.
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`mately 20 meters with selective availability (SA) off or an
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`The tuner 52 typically includes an antenna to receive the
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`accuracy in a range of 300 to 50 meters, depending upon
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`airwave radio frequency DGPS signal, a demodulator to
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`several SA parameters set by the United States Government,
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`demodulate the modulation carried by the signal, a decoder
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`with SA on. Differential GPS (DGPS) corrections may be 40
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`to decode the DGPS corrections from the modulation, and an
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`used to improve the GPS location accuracy to a DGPS
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`I/0 circuit to issue the electronic DGPS correction signal to
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`location accuracy in a range of 10 meters to a few centime­
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`the DGPS IR transmitter 54. The DGPS IR transmitter
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`ters, depending upon the methods used for determining and
`54
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`issues a responsive IR DGPS signal 55 by illuminating a
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`transmitting the DGPS corrections. In general, the DGPS
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`cone of local airspace with energy in the IR wavelength
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`corrections are determined by comparing a GPS location
`45
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`range. The DGPS radio receiver 50 includes a DGPS IR
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`computed by a GPS receiver located at a reference site with
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`receiver 56 to receive an IR control signal that may control
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`a surveyed location of the reference site. The DGPS correc­
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`the DGPS radio receiver 50. The DGPS IR transmitter
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`tions so determined are then broadcast in an airwave radio
`54
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`and the DGPS IR receiver 56 be may constructed similarly
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`frequency DGPS signal.
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`50 to the module IR receiver 18 and the module IR transmitter
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`A DGPS radio receiver 50 receives the airwave DGPS
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`16, respectively. The DGPS IR transmitter 54, the DGPS IR
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`signal having the DGPS corrections. A tuner 52 demodulates
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`receiver 56, and the IR DGPS signal 55 are included in the
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`and decodes the airwave DGPS signal and provides an
`IR link
`26.
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`electronic DGPS correction signal. Several companies, such
`In the preferred embodiment, the GPS engine 15 has the
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`as Differential Corrections Incorporated (DCI) and
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`capability of computing a geographical DGPS location
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`AccQPoint, provide real time DGPS corrections that are 55
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`based upon the GPS location information in the GPS signal
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`carried on a subcarrier of an FM signal generated and
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`and the DGPS corrections. This capability, termed "differ­
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`broadcast from certain FM broadcast stations. The correc­
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`ential ready," is available in the Trimble SV6 noted above.
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`tion information is encrypted and then modulated onto the
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`The DGPS corrections are provided to the GPS engine 15 in
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`subcarrier using a format, such as the radio data system
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`an electronic DGPS correction signal from the module IR
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`(RDS), and a data structure, such as the radio technical 60
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`commission for maritime services (RTCM) 104. The RDS
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`receiver 18 responsive to the IR DGPS signal 55. In another
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`embodiment, the executable code 38 in the processor system
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`format is described in RDS-The Engineering 2nd
`Concept,
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`32 includes instructions to compute the DGPS location
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`edition, February, 1990, published by the Technical Publi­
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`based upon the GPS location received from the module 12
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`cation Unit, BBC Engineering Training Department, Wood
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`and the DGPS corrections received in an electronic DGPS
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`Norton, Evesham, Worcestershire, WRl 1 4TF, Great Britain
`65
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`correction signal from the display IR receiver 20 responsive
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`which is incorporated herein by reference. The RTCM data
`to the IR DGPS signal 55.
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`structure is described in the RTCM Recommended
`Standards
`
`IPR2020-00409
`Apple EX1020 Page 6
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`

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`7
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`5,589,835
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`the information by illuminating the IR link 26 with signal
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`The user may operate the user entry device 44 to -enter
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`energy in the IR wavelength range. In step 84, the module
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`control information. The control information that may be
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`the IR control IR receiver 18 (DGPS IR receiver 56) receives
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`entered includes a command to switch the module 12 (and/or
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`to the electronic signal a responsive signal 23 and issues
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`of which are shown the DGPS radio receiver 50 the elements
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`module power supply power supply 58 (radio 60). In step 86,
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`within parentheses) between a normal operation mode and 5
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`the module power supply 58 (radio power supply 60)
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`standby mode by remotely enabling or disabling the oper­
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`recognizes the ID that identifies the module 12 (radio
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`com­ating power. The executable code 38 in the personal
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`information is a command receiver 50) and that the control
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`for the microproces­instructions puting display 13 includes
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`to switch power on. In step 87, the module power supply 58
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`issued by electronic signal sor 36 to receive the user device
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`power the flow of operating (radio power supply 60) enables
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`the user entry device 44 and to issue a responsive electrical
`10
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`from the module battery battery 57 (radio 59) to the GPS
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`control signal. The I/O circuit the electronic 43 receives
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`engine 15 (tuner 52) and to the module IR transmitter 16
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`control signal and issues a responsive electronic signal to the
`(DGPS IR transmitter
`54).
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`display IR transmitter a responsive 22 which issues the IR
`FIG. 2b illustrates the steps in a method for controlling the
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`control signal 23. The module IR receiver 18 (DGPS IR
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`the DGPS GPS Smart Antenna receiver module 12 and/or
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`signal receiver 56) receives the IR control 23 and issues a 15
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`power for the standby radio receiver operating 50 to disable
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`representative signal to the module power supply 58 (radio
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`mode. The steps in the method are described for the elements
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`power supply 60). The module power supply 58 (radio
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`of the module 12 (and for the elements of the radio receiver
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`enables or disables the flow power supply 60) responsively
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`50 shown within parentheses). Initially, the module 12 (radio
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`of operating power from an internal module battery
`57
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`normally. receiver 50) is operating In step 90, a user operates
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`(radio battery 59) to the module IR transmitter 18 (DGPS IR 20
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`the the user entry device 44 to enter a command to switch
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`transmitter 54) and to the GPS engine 15 (tuner 52) for
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`mode. The user module 12 (radio receiver 50) to the standby
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`normal operation or for standby, respectively. In order to be
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`by issuing a entry device 44 responds to the user operation
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`able to receive and to act upon the control information, the
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`user device electronic signal to the microprocessor 36. In
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`module IR receiver 18 (DGPS IR receiver 56) and the
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`in the step 91, the microprocessor instructions 36 processes
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`module power supply power supply 58 (radio 60) continue
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`(ID) to the executable code 38 to add an identification
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`25
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`to receive operating power from the module battery
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`control information to identify the component that is to use
`57
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`mode. It is important the standby (radio battery 59) during
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`an the information. In step 92, the microprocessor 36 issues
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`that the power consumption of the module IR receiver
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`electronic control signal including the control information to
`18
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`the electronic the I/O circuit 43. The I/O circuit 43 converts
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`(DGPS IR receiver 56) and the module power supply 58
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`control signal to a serial data format and issues a serial data
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`in the standby (radio power supply 60) be as low as practical
`30
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`signal to the display IR transmitter 22. In step 93, the display
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`mode in order to prolong the life of the module battery
`57
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`signal IR transmitter the IR control 22 broadcasts 23 to carry
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`(radio battery 59). The module power supply 58 (radio
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`the information by illuminating the IR link 26 with signal
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`operable by a an on/off switch, power supply 60) includes
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`energy in the IR wavelength range. In step 94, the module
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`human user, to override the control information to switch the
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`the IR control lit receiver 18 (DGPS IR receiver 56) receives
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`flow of operating power on and off. Typically, the module 35
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`to the electronic signal a responsive signal 23 and issues
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`computing 12, the DGPS radio receiver 50, and the personal
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`module power supply power supply 58 (radio 60). In step 96,
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`for an IR signal of "listening" display a capability 13 include
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`the module power supply 58 (radio power supply 60)
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`in the IR link 26 before beginning to transmit an IR signal
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`recognizes the ID that identifies the module 12 (radio
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`so that the IR signals do not interfere with each other.
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`information is a command receiver 50) and that the control
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`FIG. 2a illus