Note: Descriptions are shown in the official language in which they were submitted.
2~D6923U
63878-101 PATENT
_ 1 _
VEHICLE LOCATING AND COMMUNICATING METHOD AND APPARATUS
TECHNICAL FIELD
This invention relates to methods and apparatus for
locating and communicating from a central location with
vehicles traveling in various geographical areas, and more
particularly, to a method and apparatus for locating and
communicating with vehicles through use of a voice
activated mobile cellular telephone installed in the
vehicle, and visually displaying at the central location
the geographical location of each vehicle and vehicle
information automatically communicated to the central
location.
2~6~23a
- 2 -
BACKGROUND OF THE INVENTION
Historically, in industries utilizing multiple
vehicles traveling in various geographical regions, such
as in the long haul trucking industry, drivers of the
vehicles must periodically communicate with a base or home
office to report information such as present location of
the vehicle, the number of hours driven and any problems
experienced with the vehicle. In such industries where
there is a need to determine the geographical location of
a vehicle, tracking systems utilizing Loran-C receivers and
microwave transmitters have been employed for vehicle
location. Use of such equipment tends to be limited solely
to locating and tracking the vehicles. Tn many instances,
the only means of locating a vehicle in service consists
of the driver of the vehicle stopping, getting out of the
vehicle, and calling a report into the home base on a
public pay phone. To date, the cellular industry has
failed to penetrate the trucking market and other
industries where vehicle locating is desired for such
reasons as high start-up costs for obtaining terminal
equipment and high operating costs.
0
2069230
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SUMhIARY OF THE INVENTION
The locating and communicating method and apparatus
of the present invention overcome the foregoing and other
problems associated with the prior art utilizing existing
cellular telephone system services and information. A
microprocessor interrogates a cellular telephone located
in the vehicle to obtain location information received by
the cellular phone in an overhead message stream
transmitted from the particular cellular system providing
service at the time of the interrogation. A call is
initiated from the cellular telephone to a host controller
for display of the location of the vehicle on a map and
textual display of any other vehicle information
transmitted from the vehicle. A voice
activation/recognition device is connected to the
microprocessor and a hands-free microphone and a speaker
are connected to the voice activation/recognition device
to allow for hands free operation of the system by the
driver of the vehicle.
In a second embodiment of the invention, the entire
system in located crithin the vehicle. The microprocessor
interrogates the cellular phone to obtain location
information from the message stream, processes the
information, then causes the information to be displayed
on a connected display.
CA 02069230 2001-10-19
- 3a -
In accordance with one aspect of the present
invention, there is provided a system for locating and
communicating with a vehicle by means of a network of
cellular telephone systems comprising: storage/display
means including storage means and a display connected to
said storage means for displaying a map location of said
vehicle and other information transmitted to said
storage/display means; mobile cellular means for
placement in the 'vehicle; means for interrogating said
mobile cellular means to receive location information
from a particular cellular system providing service to
said mobile cellular means at the time of interrogation;
and means for initiating communication with said
storage/display means to transmit said location
information to said storage/display means from said means
for interrogating.
In accordance with another aspect of the
present invention, there is provided a system for
graphically displaying in a vehicle a geographical
location of the vehicle by means of a network of cellular
communication systems comprising: mobile cellular means;
at least one microprocessor connected to said mobile
cellular means, the microprocessor comprising a memory
for a storage of programs for controlling operation of
said system and for interrogating said mobile cellular
CA 02069230 2001-10-19
- 3b
means to receive a system identification number of a
particular cellular system providing service to the
mobile cellular means at the time of interrogation; and a
graphic display connected to said microprocessor for
displaying a map and location information.
In accordance with yet another aspect of the
present invention, there is provided a system for
locating and communicating with vehicles by means of a
network of cellular communication systems comprising: a
host controller; a cellular telephone in at least one
vehicle; at least one microprocessor connected to said
cellular telephone for interrogating said cellular
telephone to receive a system identification number of a
particular cellular system providing service to said
vehicle at the time of interrogation for determining
location of said vehicle and for initiating communication
at predetermined intervals with said host controller for
transmitting information from said microprocessor to said
host controller; a display connected to said host
controller for displaying graphically a map location of
said vehicle and for displaying textually information
transmitted from said microprocessor; voice recognition
means for voice actuation of said cellular telephone by a
vehicle operator; and a hands-free microphone to enable
CA 02069230 2001-10-19
3c -
an operator to input verbal information to said cellular
telephone.
In accordance with still yet another aspect of
the present invention, there is provided a method for
locating vehicles equipped with mobile cellular means
comprising the steps of: voice activating said mobile
cellular means to store information received verbally
from a vehicle operator; interrogating the mobile
cellular means to obtain cellular system information to
determine the location of said vehicle; establishing a
communications link between the mobile cellular means and
a storage/display means; transmitting to said
storage/display means the identity of the reporting
vehicle and information to determine location of said
vehicle; interrogating a database of the storage/display
means in response to information received from said
reporting vehicle to determine the geographic location of
said vehicle; graphically displaying on a display as a
part of said storage/display means the geographic
location of said vehicle.
In accordance with still yet another aspect of
the present invention, there is provided A method for
displaying in a vehicle the geographical location of the
vehicle equipped with a cellular communication means
comprising the steps of: interrogating said cellular
CA 02069230 2001-10-19
- 3d -
means to determine an identification number associated
with a cellular system providing communication service at
the time of interrogation; graphically displaying on a
display connected to said cellular means a map including
the area wherein said vehicle is located; highlighting on
said map the location of said vehicle; selecting by means
of a keyboard points of interest from storage means
connected to said cellular means; displaying the distance
from said selected points of interest to the location of
said vehicle; displaying the estimated travel time from
the location of said vehicle to the selected points of
interest.
~000~30
- 4 -
BRIEF DESCRIPTION OF THE DRAWINGS
For a more complete understanding of the present
invention and the advantages thereof, reference is now made
to the following Detailed Description taken in conjunction
with the accompanying Drawings in which:
FIGURE 1 i5 a diagram illustrating communication
between the vehicle and the host controller of the present
invention over a mobile cellular system;
FIGURE 2 is a block diagram of the in-vehicle
l0 portion of the locating and communicating system of the
present invention;
FIGURE 3 is a block diagram of the host controller
portion of the locating system of the present invention;
FIGURE 4 is a flow chart of the operation of the
in-vehicle portion of the locating and communicating system
of the present invention;
FIGURE 5 is a flow chart of the operation of the
host portion of the locating and communicating system of
the present invention; and
FIGURE 6 is a block diagram of the hardware of an
in-vehicle locating system incorporating a second
embodiment of the present invention.
2069230
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DETAILED DESCRIPTION
Referring now to the Drawings, and more particularly
to FIGURE 1 wherein there is shown an illustration of the
locating and communicating system of the present invention
incorporating a central data gathering device or host
controller l0 having a display 12 and a keyboard 14
connected thereto. The host controller 10 communicates as
shown by directional arrow 16 with a mobile telephone
switching office 18 in turn communicating as indicated by
directional arrow 20 with a particular cell transmitter 22
for transmitting and receiving signals from a vehicle 24
equipped with a mobile cellular transceiver (not shown)
connected to at least one microprocessor (not shown).
As shown in FTGURE 1, an overhead message stream
containing cellular system identification information,
including the SID number and, where transmitted, the cell
identification number and transmitter site coordinates, is
transmitted from the cell transmitter 22 and received by
the in-vehicle portion of the locating and communicating
system (not shown) . The signal is then read by the in-
vehicle portion of the locating and communicating system
a
to determine the existence of sufficient signal strength
for transmission from the vehicle 24. Upon reading a
sufficient signal strength and/or lapse of a predetermined
time period, a report is automatically transmitted from the
- 6 -
vehicle 24 to the cell transmitter 22, from where the
signal is carried, as indicated by directional arrow 20,
to the mobile telephone switching office 18, and from there
to the host controller 10 as indicated by directional arrow
16.
The information received is read by the host
controller 10 and looked up in a database associated
therewith and containing STD numbers, roamer numbers, cell
identification numbers, and transmitter site coordinates,
to determine the location of the reporting vehicle 24.
The location 26 of the vehicle 24 is then highlighted on
a map 28 displayed on the screen 12 connected to the host
controller 10. At that point, the operator of the host
controller 10 obtains the telephone number necessary to
initiate a telephone call to the vehicle 24 utilizing the
keyboard 14 to call up the telephone number from the
database associated with the host controller 10.
Long haul truckers must periodically report to the
base terminal or home office information such as the total
number of driver hours, any problems with the vehicle;
scheduling changes, status of the cargo, as well as any
other information needed by the home office. To maintain
current information, the locating and communicating system
of the present invention provides for automatic periodic
reporting of such information to the home office. The
2060230
report is initiated in the in-vehicle portion of the
system.
As illustrated in the block diagram of FIGURE 2,
the in-vehicle portion of the system is comprised of a
microprocessor 40 having an associated read only memory
("ROM") 42, an associated random access memory ("RAM") 44,
and an expansion port 46 for options (shown in broken
lines) including, automatic reporting of engine status, a
truck alarm system, and Loran-C positioning input to allow
for location of the vehicle using Loran-C in addition to
cellular communication.
The ROM 42 contains the necessary control programs
for operation of the in-vehicle portion of the system. The
RAM 44 is available for storing operating instructions
remotely programmable from the host controller 10.
In an attempt to monitor vehicle conditions, the
optional engine status reporting feature 43 provides for
reading by the microprocessor of engine conditions such as
temperature, engine speed, and oil pressure. In the event
of theft of the vehicle, the optional trunk alarm system
45 alerts the microprocessor to instruct the mobile
cellular transceiver 58 to initiate a call to report the
theft of the vehicle. To allow locating utilizing existing
tracking system information, the optional Loran-C
2069230
_8_
positioning input 47 provides for the receipt of Loran-C
positioning transmissions.
A power supply 48 is connected to the vehicle
battery to provide electrical energy for operating the
microprocessor 40. A start switch 50 actuates an audio
multiplexes 52 for receiving driver input through a hands
free microphone 54. The input from the hands free
microphone 54 is then passed through the audio multiplexes
52 to voice recognition and synthesis 56 for conversion to
digital form readable by the microprocessor 40.
Information is also received by the microprocessor
40 from the host controller through the mobile cellular
transceiver 58 located in the vehicle. Cellular radio
signals are received by the mobile cellular transceiver 58
connected to a vehicle antenna 60. The signals are then
transmitted over the cellular phone bus 62 through the
audio multiplexes 52 and a smart modem 72 to the
microprocessor 40. The microprocessor 40 is connected to
the audio multiplexes 52 through the smart modem 72 to
allow extraction of the digital informatian from the analog
signal and for modulation of the information transmitted
from the microprocessor 40. An interface 74 provides the
necessary protocol for communication between the
microprocessor 40 and the mobile cellular unit.
2000~~0
_ g _
In the event of audio communication between the
operator of the host controller and the driver, the signals
are transmitted from the transceiver 58 over the cellular
phone bus 62 to the handset 64 of the mobile cellular unit.
If the driver of the vehicle elects to use the hands free
microphone 54, instead of the handset 64, for audio
communication with the operator of the host controller, the
audio communication travels from the cellular phone bus 62
through the audio multiplexer 52 to an amplifier 66 for
broadcast to the vehicle driver through a speaker 68. The
volume of the broadcast is regulated by a volume control
70 controlling the amplifier 66.
Operating energy is provided to the amplifier 66
and cellular telephone transceiver 58 from the vehicle
ignition. When the driver is verbally communicating over
the cellular telephone, he may speak through either the
hands-free microphone 54 or may lift and speak through the
handset 64. For storage of information through voice
recognition, the hands-free microphone may be used.
As shown in~the block diagram of FIGURE 2, the
microprocessor 40 connected to the mobile cellular unit has
connected thereto a calendar and clock 49 for documenting
the date and time of storing and/or transmitting
information. A report interval timer 51 provides for
determining when to initiate a call to the host controller
206~2~0
- 10 -
based upon the expiration of a predetermined time period
remotely programmed by the host controller and stored in
the RAM 44.
To inhibit calls made from the mobile unit to
numbers unauthorized by the home office, the microprocessor
40 has a restricted phone usage function 53 that searches
a list of authorized phone numbers remotely programmed by
the host controller and stored in the RAM 44. The
numerical keys of the handset of the cellular phone are
disabled. Thus, the authorized numbers may only be
accessed through voice command. If the number entered
through voice command is not contained in the list of
authorized numbers, the call is automatically inhibited.
Similarly, the authorized systems look-up table 55 prevents
initiation of a call cahen the SID number contained in the
message stream at the time of interrogation is not
contained within said look-up table.
The voice recognition operation 57 of the
microprocessor 40 provides for receiving and storing of
information in a memory connected to the mobile cellular
transceiver upon receipt of verbal input from the driver
of the vehicle. In addition to reading and transmitting
information, the microprocessor 40 has tracking log
capabilities 59 for recording and storing vehicle
2~~9~30
- 11 -
information for extended reporting periods for subsequent
report compilation.
As shown in the block diagram of FIGURE 3, the
central data gathering device or host controller portion
of the locating system of the present invention comprises
a host controller 90 connected to a smart modem 92 to allow
communication between the controller 90 and any number of
telephone lines dedicated for vehicle reporting only.
Associated with the host controller 90 is an optional auto
dial feature 94 (shown in broken lines) for initiating
calls over a watts line 96. Calls are initiated to, as
well as calls received from, the vehicle over the watts
line 96.
Connected to the host controller is at least one
terminal 98. In the case of larger companies, an optional
system expansion configuration 104 (shown in broken lines)
utilizing an existing customer processing system 106 and
existing dispatch terminals 108, may be utilized to reduce
system installation costs. Each terminal 98 has a screen
100 for displaying a map, location information regarding
each reporting vehicle, and textual information reported
t
by each vehicle. A keyboard 102 is connected to each
terminal 98 for remote programming of authorized telephone
numbers for storage in the RAM 44 associated with the
microprocessor 40, to allow the host operator to access
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- 12 -
databases containing telephone numbers for the various
locations of the reporting vehicles, to allow menu
selection, and to allow remote programming of the report
time interval in the microprocessors located in each of the
vehicles.
Through an error correcting protocol, the host
controller 90 instructs the microprocessor 40 through the
mobile cellular transceiver 58 to transmit information to
the host controller. The host controller 90 receives said
input through the smart modem 92 from the reporting
vehicle. The information is read by the host controller
90 and location information looked up in a database
associated therewith. The location information of the
vehicle is then displayed on the screen 100 of the terminal
98. An in-service area alert is actuated to advise the
operator of the host controller 90 of the entry of a
reporting vehicle into a strong signal reporting area to
allow the operator of the host controller to initiate
contact with the reporting vehicle.
In the event the operator of the host controller
needs to initiate contact with a vehicle, requiring
location of the vehicle, between reporting periods, the
operator of the host controller 90 pulls up information
regarding the last reporting time and location of the
vehicle. Through use of the connected keyboard 102, the
2069230
- 13 -
operator then inputs the final destination of 'the vehicle.
The host controller 90 then determines the approximate
route of the vehicle, calculates the average speed of the
vehicle using previously reported driver hours and distance
traveled to determine the approximate distance traveled
since the last reporting period, thereby determining the
approximate location of the vehicle. Cellular numbers for
a predetermined area surrounding the approximate location
of the vehicle are looked up in the database and are
automatically dialed by the host controller 90 at
predetermined intervals until contact is made with the
vehicle.
The method of transmission from the in-vehicle
portion of the locating system of the present invention is
shown the flow chart of FIGURE 4, with reference to the
block diagram of FIGURE 2. Initially, the microprocessor
40 determines if a predetex-mined period of time has elapsed
(at 120), with the time interval having been remotely
programmed by the host controller 10. If the interval has
not lapsed, the microprocessor 40 continues to cycle until
such time as a determination is made that the predetermined
time period has elapsed. At that point, the microprocessor
40, through the interface 74, interrogates (at 122) the
mobile cellular transceiver 58 located in the vehicle to
read the signal strength being received by the mobile
2069230
- 14 -
cellular transceiver 58 to determine whether the vehicle
is in a cellular system service area (at 124). If the
vehicle is in a cellular system service area, the
microprocessor will read the SID number (at 126) from the
information received by the mobile cellular transceiver 58
from the overhead message stream, and will look up the SID
number (at 126) from the database installed therein to
determine the appropriate dialing method to initiate a call
from the mobile cellular transceiver to the host
controller.
The microprocessor 40 then makes a determination as
to whether the microprocessor has been remotely programmed
by the host controller 10 to authorize the vehicle to dial
out in the particular cellular system service area (at 128)
providing service to the mobile cellular unit. If the call
is authorized, the microprocessor 40 then determines (at
130) whether the signal strength being received by the
mobile cellular transceiver 58 is sufficient to authorise
initiation of a call from the vehicle to the host
controller Z0. If the vehicle is not authorized to dial
out of the service area, or if the signal strength is not
sufficient, the microprocessor 40 will return to the step
of determining whether the vehicle is in a service area (at
124) and will continue through each of the steps (at 126,
128, and 130) until a determination is reached that the
2069230
- 15 --
vehicle is authorized to dial out of the service area and
that the mobile cellular transceiver 58 is receiving an
acceptable signal strength for initiating a call. At that
point, the microprocessor will instruct the mobile cellular
unit to dial out (at 132).
After the number has been dialed, the microprocessor
40 determines whether the call has been completed to the
smart modem 92 (at 134) connected to the host controller
90 at the terminal or home office. If a determination is
made that the call has not resulted in a connectiOTl with
the smart modem 92, the microprocessor 40 instructs the
mobile cellular unit to hang up (at 136). If, however, the
call has gone through, the microprocessor 40 receives
instructions from the host controller 90 to transfer
predetermined information to the host controller. In
accordance with said instructions, the microprocessor 40
transmits (at 138) the particular vehicle identification
number, the location information obtained from the overhead
message stream through interrogation of the mobile cellular
unit, and telemetric data regarding such 'information as
vehicle system status, driver hours, and any other
information stored in the memory associated with the mobile
cellular transceiver 58.
Once the transfer of information is complete, the
microprocessor 40 receives a command from the host
2069230
- 16 -
controller 90 to disconnect (at 140). Upon receipt of the
command to disconnect, the microprocessor instructs the
mobile cellular transceiver 58 to disconnect (at 124) the
call to the host controller 90.
After disconnect or hanging up of the call to the
host controller 90, the microprocessor 40 reloads the
interval timer (at 144) to determine the lapse of the
predetermined time period in which to initiate the next
automatic report from the vehicle to the host controller
90. Each time the predetermined time period elapses, each
of the steps set forth in the flow chart of FIGURE 4 are
automatically performed to initiate transmission of a
report from the microprocessor through the mobile cellular
unit over the cellular telephone system to the host
controller where the information is read, looked up,
displayed, and stored by the host controller for subsequent
compilation into a detailed report covering varying time
periods and any number of reporting vehicles.
Referring now to FIGURE 5, there is shown a flow
chart of the operation of the central data gathering device
or host controller portion of the locating system. As
illustrated in FIGURE 5, with reference to the block
diagram of FIGURE 3, when a call is initiated by a
reporting vehicle to the host controller 90, the phone
connected to the host controller rings (at 200) and is
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- 17 -
answered (at 202). Upon connection with the host
controller 90 (at 204) through the smart modem 92 the host
controller 90 interrogates (at 206) the microprocessor of
the reporting vehicle to determine the vehicle
identification number. The host controller 90 then looks
up the identification number to determine (at 208) whether
the identification number is valid. If the vehicle
identification number is invalid, the host controller 90
will instruct the mobile cellular phone in the vehicle to
disconnect (at 210), resulting in the mobile cellular unit
hanging up on the call (at 212).
Upon determining that a valid vehicle identification
number has been reported, the host controller 90 instructs
the in-vehicle microprocessor (at 214) to transmit
information regarding the location of the reporting
vehicle. Upon receipt of the location information (at
216), the host controller 90 instructs (at 218) the
microprocessor to transmit telemetric data regarding
various vehicle systems. If the host controller fails (at
220) to receive data from the vehicle, it will instruct
(at 222) the mobile cellular unit of the vehicle to
f
disconnect and initiate a new call. If the information is
received by the host controller 90, the screen 100 of the
terminal 98 is updated (at 224) to display the current
location information for the reporting vehicle.
2U6923~
- is -
The information is also stored (at 226) for
subsequent compilation into report form. Thereafter, the
host controller 90 instructs the remote cellular unit to
disconnect the call (at 210). The call is disconnected and
the cycle restarted upon the receipt of a call from the
mobile cellular unit.
Thus, operation of the locating and communicating
method and apparatus as described combines locating and
communicating capabilities in a system utilizing existing
cellular telephone system services and information. The
cellular system currently in use today consists of many
transmitter sites in and around cities, each constituting
a cell. Some of the transmitter sites are as close to one
another as one mile or less in dense traffic areas. In the
outermost regions of a service area, the cell transmitter
sites work at higher power levels and are spaced further
apart. A network grid across a city is formed by the
adjoining cells to provide uninterrupted communication for
a mobile telephone unit using cell site handoff techniques
as the vehicle travels between cells.
When in a coverage area, the mobile cellular unit
receives an overhead message stream continuously
transmitted from each cell transmitter site. The mobile
cellular unit automatically tunes to the strongest signal,
that being the signal transmitted from the nearest cell
2069230
_ 19 _
transmitter site. In this manner, the mobile cellular unit
is able to receive instructions from the cellular network
as to when and where the mobile unit should re--tune to
another voice channel in the next nearest transmitter site
S before the vehicle has moved out of range of the last
transmitter site.
The location apparatus of the present invention
includes a microprocessor connected to a modem in turn
connected to an 800 MHz mobile cellular radio transceiver
in each vehicle. At the trucking base terminal or home
office, a host controller is connected through a modem to
the cellular transmitter fox communicating with the mobile
cellular unit and microprocessor installed in the vehicle.
As the vehicle travels from cellular system to cellular
system and from cell to cell within each cellular system,
the mobile cellular unit receives overhead message streams
transmitted from cellular transmitter sites located in the
individual cells. Information such as the particular SID
number, and the number of a particular cell from where the
overhead message stream is being transmitted is contained
in the message stream. The microprocessor connected to the
mobile cellular unit periodically interrogates the unit to
obtain the SID number and other location information
carried in the overhead message stream at the time of the
interrogation. In the event longitude and latitude
20~9~3~
- 20 -
coordinates of the physical location of the particular
transmitter site transmitting the overhead message stream
are added to the information -transmitted, the
microprocessor is capable of interrogating the mobile
cellular unit to determine the longitude and latitude
location of the vehicle.
Strength of the radio signal carrying the message
stream is also determined by the microprocessor at the time
of interrogation. If the microprocessor reads a certain
minimum radio signal strength and/or a predetermined period
of time has elapsed, the microprocessor automatically
instructs the cellular radio transceiver to initiate a
telephone call to the host controller on the particular
cellular system providing service at that time.
At the base terminal or home office, the host
controller receives the telephone call and instructs the
microprocessor, via a proprietary error correcting
protocol, to transmit information over the cellular system
to the host controller. The host controller requires the
transmission of such information as the SID number, and the
cell number and transmitter coordinates, received by the
cellular transceiver from the overhead message stream, and
in some cases requires transmission by the driver of the
vehicle of information stored in a memory connected to the
mobile cellular unit.
~os~~~a
- 21 -
Information stored by the vehicle driver includes
such information as the identity of the vehicle, the number
of hours the driver has been at the wheel, or other
information based upon the needs of the locating and
communicating system user. A voice actuation feature and
a hands free microphone connected to the mobile cellular
transceiver allow the driver to automatically enter
information regarding driver hours, vehicle identity and
other requested information without having to lift the
ZO handset.
Upon receipt of the information, the host controller
looks up the SID number in a database associated therewith.
to determine the geographical location of the SID number,
thereby determining the location of the vehicle. The
vehicle location is then highlighted on a map displayed on
a screen connected to the host controller. Additional
information regarding driver hours, location of the
vehicle, or any other requested information, is displayed
in text on the screen whereon the map indicating
geographical location is displayed. Thus, the operator of
the host controller can immediately see the location of the
reporting vehicle and read pertinent information reported
by the vehicle.
Information enabling the host controller operator
25~ to initiate a telephone call to establish voice
2069230
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communication with the vehicle driver is also contained in
the database associated with the host controller.
Information reported from the vehicle is stored in a memory
associated with the host controller for subsequent review,
analysis, or compilation into reports covering varying time
periods and numbers of vehicles.
The database installed in the host controller also
contains information regarding cell identification numbers
and longitude and latitude coordinates for a specific
transmitter site within the cells in the event that a
particular cellular system includes such information in the
overhead message stream. By adding an identification
number of the transmitting cell and the longitude and
latitude coordinates for the cell transmitter site to the
message stream, the location of the vehicle is more
accurately determined. Assuming that the mobile cellular
unit would always tune to the nearest transmitter, the
accuracy of the vehicle location would be approximately a
radius equal to one-half the distance between the
transmitter site to which the mobile unit is tuned and the
next nearest site. Thus, a more accurate geographical
location of the vehicle is determined.
By utilizing a voice activated mobile cellular unit,
the base terminal or home office accurately monitors the
location of each vehicle by means of conventional
2009230
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triangulation location techniques using cellular
transmitters located in adjacent cells in a cellular
system, as well as obtains voice contact with the driver
of the vehicle at any time, utilizing existing cellular
systems and system information. Thus the locating and
communicating system alleviates the need for systems and
equipment limited only to vehicle tracking, increases the
ease of driver/base accessibility, and avoids driver
distraction while communicating with and reporting to the
base terminal or home office.
In a locating system incorporating a second
embodiment of the present invention, as shown in the block
diagram of FIGURE 5, the entire apparatus of the locating
system is contained within a vehicle to allow the driver
to ascertain the current location of the vehicle utilizing
the information transmitted in the cellular system overhead
message stream. The in-vehicle locating system comprises
a microprocessor 250 having an associated read only memory
252 containing a control program, an associated random
access memory 254 for storing data input by the driver, and
an associated external memory port 256 for receiving plug-
in modules containing maps, directories, and other
information regarding a particular geographical area.
A graphic display 258 for showing the geographical
location of the vehicle and display of textual information
~0~9230
- 24 -
is connected to the microprocessor 250 in the vehicle. An
interface 260 provides for communication between the
microprocessor 250 and the graphic display 258. A smart
modem 251 connects the microprocessor 250 through the audio
multiplexes 259 to the mobile cellular unit to allow
communication between the microprocessor and the mobile
cellular unit.
As with the first embodiment of the present
invention, the microprocessor 250, through use of an
interface 264 automatically interrogates or the driver may
select a menu function through use of a keyboard 262
connected to the microprocessor to initiate interrogation
of the mobile cellular transceiver 266 over the cellular
phone bus 268 to obtain location information from the
overhead message stream received by the mobile cellular
unit through an antenna 270. Upon receipt of the location
information from the overhead message stream, the
microprocessor 250 looks up the information in a database
associated with the microprocessor 250 to determine the
geographical location of the vehicle. The geographical
location is then highlighted on a map displayed on the
a
geographic display 258 connected to the microprocessor 250.
The particular map displayed depends upon the plug
in modem presently installed in the external memory port
256 connected to the microprocessor 250. Through use of
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the keyboard 262, 'the driver may select particular points
of interest from the various directories contained in the
plug-in modules. Various menu selections allow the driver
to initiate calls to the particular points of interests,
highlight the location of the points of interest on the map
displayed, and receive textual information regarding the
estimated travel time to reach the selected points of
interest from the present vehicle location. Further,
through use of the keyboard 262, the driver may zoom or pan
the map displayed on the graphic display 258 to obtain more
detailed information.
As with the first embodiment of the present
invention, the mobile cellular unit is equipped with a
handset 272, and has attached a voice
recognition/activation device 274 and a hands-free
microphone 276 to allow operation of the locating system
with less driver distraction and safer vehicle operation.
As with the locating system incorporating the first
embodiment of the present invention, the in-vehicle
locating system incorporating the second embodiment of the
present invention utilizes the system identification
number of the particular cellular system providing service,
the cell identification number where the mobile cellular
unit is receiving the overhead message, and the longitude
and latitude coordinates of a particular cell transmitter
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site, all of which may be transmitted in the overhead
message stream from a particular cell transmitter site.
Although preferred embodiments of the invention have
been illustrated in the accompanying drawings and described
in the foregoing Detailed Description, it will be
understood that the invention is not limited to the
embodiments disclosed, but is capable of numerous
rearrangements and modifications of parts and elements
without departing from the spirit of the invention.
