United States Patent
`
`[19]
`
`[11] Patent Number:
`
`5,526,401
`
`[45] Date of Patent: Jun. 11, 1996
`Roach, Jr. et a1.
`
`
`
`U5005526401A
`
`[54]
`
`[75]
`
`[73]
`
`[21]
`
`[22]
`
`[62]
`
`[51]
`[52]
`[58]
`
`[56]
`
`NIETHODS AND APPARATUS FOR
`ACKNOWLEDGING A PAGING MESSAGE
`VIA A CELLULAR NETWORK CONTROL
`CHANNEL
`
`Inventors: Peter O. Roach, J1:, Atlanta; Edward
`I. Comer, Marietta; Maurice S. Laster,
`Atlanta; Charles M. Link, II, Roswell,
`all of Ga.
`
`Assignee: BellSouth Corporation, Atlanta, Ga.
`
`Appl. No.: 331,794
`
`Filed:
`
`Oct. 31, 1994
`
`Related U.S. Application Data
`
`Division of Ser. No. 212,039, Mar. 11, 1994.
`
`Int. Cl.6 ..................................................... .. H04Q 7/24
`
`.. 379/59; 379/57; 455/33.l
`U.S. C1.
`............ ..
`Field of Search ................................ .. 379/57, 58, 59,
`379/63; 455/33.1, 54.1; 340/82544, 311.11
`
`References Cited
`
`U.S. PATENT DOCUMENTS
`
`OTHER PUBLICATIONS
`
`European Telecommunication Standard—Draft pr ETS 300
`537, “European Digital Cellular Telecommunications Sys-
`tem (Phase 2); Technical Realization of SHort Message
`Service Call Broadcast (SMSCB)”, European Telecommu-
`nications Standards Institute, Oct. 1993,
`European Telecommunication Standard—Draft pr ETS 300
`536, “European Digital Cellular Telecommunications Sys—
`tem (Phase 2); Technical Realization of the short Message
`Service (SMS) Point to Point (PP)”, European Telecommu—
`nications Standards Institute, Oct. 1993,
`The GSM System for Mobile Communications, Michel
`Mouly
`and
`Marie—Bemadette
`Pautet
`ISBN:
`2—9507190—0—7, @1992; pp. 56—59.
`“Mobile Cellular Telecommunications Systems” William C.
`Y. Lee, pp. 74—80, 1989.
`
`Primary Examiner—Cnis Kuntz
`Assistant Examiner—William G. Trost
`Attorney, Agent, or FirmiJones & Askew
`
`[57]
`
`ABSTRACT
`
`A paging acknowledgement system is provided for commu-
`nicating both (1) paging messages and (2) acknowledgement
`messages to confirm reception of the paging messages. The
`paging acknowledgement system includes at least one com—
`munications system, remote communications devices, and at
`least one MSC of a CMR system. In response to a paging
`message from a paging party, the communications system
`transmits data messages corresponding to the paging mes—
`sage via a communications link. The data message contains
`the type of data that is normally supplied with a conventional
`paging message and an acknowledgment code that uniquely
`identifies said data message. A remote communications
`device responds to a data message containing its particular
`address by transmitting an acknowledgment message con—
`taining the acknowledgment code to the MSC via a cellular
`network control channel of the CMR system. The MSC
`forwards the acknowledgment message to the communica-
`tions system via a first communications link. The data
`collection system confirms reception of the data message by
`comparing the acknowledgment code of the acknowledg—
`ment message to the acknowledgment codes associated with
`the paging messages.
`
`8/1976 Akerberg .
`3,973,200
`4,172,969 10/1979 Levine et a1.
`4,263,480
`4/1981 Levine.
`4,644,351
`2/1987 Zabarsky et a1.
`4,646,082
`2/1987 Engel et al,
`.
`4,750,197
`6/1988 Denekarnp et a].
`4,814,763
`3/1989 Nelson et a1.
`.
`4,823,123
`4/1989 Siwiak.
`.
`4,825,193
`4/1989 Siwiak et al.
`4,825,457
`4/1989 LebowitZ ................................ .. 379/59
`4,868,560
`9/1989 Oliwa et al.
`.
`4,875,038
`10/1989 Siwiak et a1.
`4,882,579 11/1989 Siwiak.
`.
`4,891,637
`2/1990 Siwiak et a1.
`4,928,096
`5/1990 Leonardo et a1.
`4,940,963
`7/1990 Gutman et a1.
`.
`4,993,059
`2/1991 Smith et a1.
`............................ .. 379/59
`
`.
`
`.
`
`.
`
`.
`
`379/58
`
`(List continued on next page.)
`
`79 Claims, 9 Drawing Sheets
`
`
`
`
`
`F MOBILE
`l SWITCHING
`cranes (MSC)
`
`*
`
`24‘
`
` -- 40'
`
`i
`i
`
`COLLECTION
`DATA
`SYSTEM
`
`1 ’
`
`Fm
`COMMUNICATIONS
`um
`
`’
`
`, v 774
`
`PAGING
`MESSAGES
`
`
`
`GH EXHIBIT 1008
`GH EXHIBIT 1008
`
`

`

`5,526,401
`
`Page 2
`
`10/1992 Eastmond et a1.
`11/1992 Jasinski.
`12/1992 Levanto et 21.1..
`6/1993 Brown Ct :11.
`........................ .. 379/63
`8/1993 Flanders etal.
`........ 455/54.1
`8/1993 Grube eta]. .
`379/57
`4/1994 Dai el al.
`. 455/541
`4/1994 Michalon et a1.
`8/1994 Aron ct a1.
`.............................. .. 379/58
`
`
`
`...................... .. 379/57
`
`US. PATENT DOCUMENTS
`
`4/1991 Jasinski-
`5,005,014
`9/1991 Kuznicki et al.
`5,047,763
`5/1992 Metroka ct a1.
`........................ .. 379/58
`5,117,449
`6/1992 Moore.
`5,124,697
`8/1992 Jasinski 6131..
`5,142,279
`9/1992 Freedland e131,.
`5,148,473
`5,153,582 10/1992 Davis.
`
`5,153,903
`5,162,790
`5,175,758
`5,222,123
`5,239,294
`5,239,678
`5,307,399
`5,307,509
`5,341,410
`
`

`

`
`
`mama'S'fl
`
`966T‘II11111“
`
`6J0Ileans
`
`Iov‘9zs‘s
`
`
`
`
`
`MOBILE
`SWITCHING
`
`CENTER (MSC)
`
`[———I
`
`(scijnéa
`
`x/29VFI
` PUBLIC
`
`SWITCHED
`TELEPHONE
`NETWORK
`
`-‘44
`MEMORY
`
`
`
`TELEPHONE FACILITIES
`
`
`
`
`
`
`
`DATA
`COLLECTION
`PROCESSING
`SECOND
`
`SYSTEM
`SYSTEM
`COMMUNICATIONS
`
`
`
`LINK
`
`
`
`FIRST
`COMMUNICATIONS
`LINK
`
`
`
`FIG. 1
`
`

`

`Predetermined Identifying Characteristic
`
`FIG. 2
`
`Controller
`
`74
`
`’50
`
`Selected Data (in Hex)
`
`
`
`mama'S'fl
`
`966I‘II'Imf
`
`61"Z199‘IS
`
`Iov‘9zs‘s
`
`/
`
`Data Message Record Content
`87052691
`
`0001234567
`
`54
`
`
`
`

`

`US. Patent
`
`Jun. 11, 1996
`
`Sheet 3 of 9
`
`5,526,401
`
`
`Receive Data
`
`
`
`Message via
`Control Channel
`
`
`
`
`
`210
`
`274
`
`
` Receive MIN
`Associated with a
`
`
`
`
`"Home" Unit?
`
`
`NO
`
`216
`
`YES
`
`Register
`
`Home Unit
`
`Data Mesage
`Transmitted by
`a “Roamer”
`
`2 73
`
`220
` Roamer's
`
`MlN Present in
`the Database?
`
`
`
` Transmit
`
`
`Data Message
`to Foreign System
`
`l
`
`Add
`Roamer’s MIN
`
`to Database
`
`
`
` Receive
`Instruction to Delete ,
`
`Roamer‘s MlN
`
` YES
`
`from Database?
`
`FIG. 5
`
`230
`
`Delete
`
`Information
`
`204
`
`206
`
`208
`
` Monitor
`
`Remote Data
`
`
`
`Source
`
`202
`
` Record
`
`
`Selected
`Data
`
`
`
`
`
`Prepare
`Data Packet
`
`
`
`Transmit
`
`Data Message
`
`Branch to MSC
`
`Routine
`
`(A in FIG. 5)
`
`FIG. 4
`
`
`
`

`

`U.S. Patent
`
`Jun. 11, 1996
`
`Sheet 4 of 9
`
`240
`
`242
`
`
`
` Predatermined
`Time Period Expire?
`
`YES
`
`f Output
`244
`Clock Signal
`
`Prepare
`
`24g— Data Packet
`
`
`
`
`
`Monitor
`
`Busy Idle Bits
`and
`
`Calculate "n"
`
`Average
`
`248
`
`FIG. 6
`
`250
`
`
`Computed
`
`"it" Average < Stored
`Running
`
`Average?
`
`
`YES
`
`Transmit
`
`252 Data Message
`
`

`

`
`
`mama'S'fl
`
`:4
`F
`FH
`\D
`\a
`Ox
`
`m
`E
`
`a a
`
`,
`\a
`
`Iov‘9zs‘s
`
`PAGl NG
`MESSAGES
`
`
`
`
`
`
`
`
`DATA
`
`
`
`COLLECTION
`FIRST
`
`COMMUNICATIONS
`SYSTEM
`LINK
`L ------------------------------------------------------------------------------------- -‘
`
`II.0 \I
`
`COMMUNICATIONS
`NETWORK
`(PSTN)
`
`PAGING
`TERMINAL
`
`151
`
`:
`
`‘
`
`5
`
`'
`
`22 I
`'
`
`
`
`MOBILE
`SWITCHING
`CENTER (MSC)
`
`

`

`US. Patent
`
`Jun. 11, 1996
`
`Sheet 6 of 9
`
`5,526,401
`
`Data Message Record Content
`
`4047654321
`
`0001234567
`
`CALL 777-6666
`
`
`
`
`762
`
`164
`
`Acknowledgment
`Code
`
`760
`
`
`
`766
`
`Paging Data
`
`FIG. 8
`
`Acknowledgement Message Record Content /’ 768
`
`
`
`
`
`
`0001234567
`
`1 1 1222333444
`
`172
`
`
`
`
`Operation Data
`
`Acknowledgement Code
`
`FIG. 9
`
`

`

`
`
`filmed'S'n
`
`
`
`9661‘11WI
`
`6J0Lwas
`
`1017‘9ZS‘S
`
`
`
`
`
` MOBILE
`
`SWITCHING
`PAGI N G
`PAGING
`TERMINAL
`M ESSAG ES
`CENTER (MSC)
`
`
`
`
`
`
`COLLECTION
` FIRST
`
`
`5
`SYSTEM
`;
`
`COMMUNICATIONS
`LINK
`
`

`

`
`
`mama'S'fl
`
`966I‘II'[mf
`
`6J08mus
`
`1017‘9ZS‘S
`
`180
`
`186
`
`nl
`
`
`
`E
`3
`
`Cellular
`Receiver
`
`Cellular
`
`Transmitter
`
`
`Data; Channel
`
`Paging
`
`Receiver
`
`
`
`
`184
`
`.
`:
`i ————————————————————————————————————————— -—'——————————————————————————————— —~'\ 7152
`Remote Communications Device
`
`FIG. 11
`
`

`

`US. Patent
`
`Jun. 11, 1996
`
`Sheet 9 of 9
`
`5,526,401
`
`276
`
`
`i
`FORWARD
`ACKNOWLEDGMENT
`
`MESSAGE
`
`
`278
`
`ACKNOWLEDGMENT
`
`CODE = STORED
`
`ACKNOWLEDGMENT
`
`CODE 7
`
`
`
`
`
`
`NO
`
`
`
`260
`
`262
`
`264
`
`265
`
`266
`
`268
`
`270
`
`272
`
`274
`
`RECEIVE
`
`PAGING
`
`MESSAGE
`
`PREPARE
`
`DATA
`
`MESSAGE
`
`STORE
`ACKNOWLEDGEMENT
`
`CODE
`
`TRANSMIT
`
`DATA
`
`MESSAGE
`
`RECEIVE
`
`DATA
`
`MESSAGE
`
`PREPARE
`
`ACKNOWLEDGEMENT
`
`MESSAGE
`
`TRANSMIT
`
`ACKNOWLEDGEMENT
`
`MESSAGE
`
`RECEIVE
`
`ACKNOWLEDGEMENT
`
`MESSAGE
`
`
`
`OF PAGING
`
`CONFIRM RECEIPT
`
`CONFIRMATION
`
`MESSAGE
`
`
`FIG. 12
`
`

`

`5,526,401
`
`1
`METHODS AND APPARATUS FOR
`ACKNOWLEDGING A PAGING MESSAGE
`VIA A CELLULAR NETWORK CONTROL
`CHANNEL
`
`This is a division of application Ser. No. 08/212,039,
`entitled “Methods and Apparatus For Communicating Data
`Via A Cellular Network Control Channel,” filed Mar.
`l1,
`1994 by Peter Owen Roach, Jr., Edward lrby Comer, Mau-
`rice Scott Laster, and Charles Martin Link II.
`
`TECHNICAL FIELD
`
`The present invention relates generally to data commu-
`nications systems and more particularly relates to a method
`and apparatus for communicating data via a cellular network
`control channel of a cellular mobile radiotelephone system.
`
`BACKGROUND OF THE INVENTION
`
`In recent years, the communications industry has shown
`a growing interest in various types of wireless communica—
`tions systems for communicating voice and/or data between
`numerous remote sites and a central
`location. It is well
`recognized that the use of a dedicated telephone facility for
`a conventional telephone system is not a convenient or
`economical option for all communications applications. For
`example, individuals who must be away from their base of
`operations have a need to conveniently and efficiently com-
`municate with their base. Likewise, for many industrial
`applications, a central data collection site has a need for
`acquiring information from a variety of remotely located
`monitoring devices that collect data about the operation or
`performance of equipment. To overcome the limitations of
`the conventional
`telephone system, a two-way wireless
`communicatiOns link is often necessary to permit a response
`to a communication initiated from another location. In an
`attempt to solve the problem of Supplying a response to an
`initial communication, the industry has offered various wire—
`less communications systems,
`including two—way radios,
`mobile radiotelephones, and paging systems.
`A conventional radio communications system uses a base
`station transceiver located at a site for favorable radio
`propagation and a set of transceivers typically located in
`vehicles, such as for police or trucking dispatching systems,
`or at remote equipment sites that communicate data in
`response to a command signal from the base station trans-
`ceiver. Most radio communications systems are useful for
`conducting communications between short distances, such
`as within the boundaries of a town or city, via a very high
`frequency (VHF) radio link.
`Although conventional radio communications systems are
`useful for specialized communications applications,
`two—
`way radios are not widely accepted for general purpose
`communications. The use of two-way radios is generally
`regulated by the Federal Communications Commission
`(FCC) and the allocated frequency spectrum is relatively
`limited. Furthermore,
`the quality of communications is
`subject to the propagation conditions between communica—
`tions sites. Two—way radio equipment is generally large and
`heavy and, as a result, is unlikely to be carried by a user at
`all—times or to be installed in small or existing equipment.
`Another form of two—way communications is a cellular
`mobile radiotelephone (CMR) system, which is connected to
`the extensive public switched telephone network (PSTN)
`and permits communications between a mobile radiotele—
`phone user and anyone with a conventional telephone (or
`
`10
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`15
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`
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`
`2
`another radiotelephone). Typical CMR systems are charac-
`terized by dividing a radio coverage area into smaller
`coverage areas or “cell” using low power transmitters and
`coverage-restricted receivers. As shown in US. Pat. Nos.
`3,906,166 and 4,268,722, the limited coverage area enables
`the radio channels used in one cell to be reused in another
`cell. As a cellular mobile radiotelephone within one cell
`moves across the boundary of the cell and into an adjacent
`cell, control circuitry associated with the cells detects that
`the signal strength of the radiotelephone in the just—entered
`cell is stronger, and communications with the radiotelephone
`are “handed—off” to the just—entered cell. Thus, a CMR
`system can supply two-way communications for an array of
`cells, thereby supplying communications for a much wider
`area than conventional two-way radios.
`Conventional radiotelephones generally offer both voice
`and data communications capabilities and, accordingly, the
`radiotelephone service is generally supplied at a cost that is
`commensurate with the combined voice and data services.
`Nevertheless, this combination of both voice and data com—
`munications may exceed a user’s requirement for commu—
`nicating by only voice or data. In addition, real—time voice
`or data communications is not always desirable by a user
`who wishes only to receive a message without having a
`current activity disturbed. Similar to two—way radios, the
`frequency spectrum for the CMR system radio channels,
`particularly voice channels, is a limited resource.
`Paging systems include pagers, which are miniature
`receivers, and at least one paging terminal having a trans—
`mitter that covers a selected geographic area containing
`numerous pagers. A pager is generally tuned to a particular
`tone or data bit-modulated radio frequency that is shared
`with many other pagers. A particular sequence of tones or
`data bits is used as an address or the identification of a
`selected pager. Reception of the particular sequence acti-
`vates an acoustic, tactile, or visible alert, thereby indicating
`that a call has been placed to the paging terminal from a
`telephone connected to the PSTN and generally communi—
`cated via the transmitter to the pager. Depending upon the
`complexity of the pager, the paging device may receive a
`voice or a data message following the alert, or the alert alone
`may simply indicate to the user that a call was made and a
`prearranged action should be taken. This type of pager forms
`a one-way messaging system because it does not permit the
`party initiating the page to know if the page has actually
`been received by the addressed pager.
`To respond to a page received via the conventional
`one-way paging system, the paged party typically must find
`an available conventional telephone and initiate a telephone
`call to the party that initiated the page. Alternatively, the
`paged party can place a responsive call by use of a mobile
`radiotelephone, if available. In recognition of this problem
`of separate pager and radiotelephone devices, US. Pat. No.
`5,148,473 describes a pager and radiotelephone apparatus
`having the combination of a radio pager section and a
`cellular radiotelephone section. To answer a page, the user
`simply places a call via the CMR system. The pager also
`allows the user to screen incoming call to determine which
`of the received messages to retum, thereby eliminating the
`CMR system service costs associated with unwanted calls.
`However, any acknowledgment of a received page by this
`apparatus requires use of the relatively limited spectrum for
`voice channels of the CMR system.
`Paging systems having two—way communications capa—
`bility for receiving a page and transmitting an acknowledge
`receipt of a page are also known. One such system enables
`a pager having acknowledgment capability to immediately
`
`

`

`5,526,401
`
`3
`communicate a response to the calling party after receiving
`the initial page contact. The response may be a voice,
`numeric, or alphanumeric message informing the originator
`of the page communication that the message was success-
`fully received by the page, and may further offer a reply to
`the received message. This page acknowledgment system
`generally includes a single central transmitter covering a
`certain geographic area and one or more acknowledgment
`system receivers for receiving acknowledgment signals
`from the pagers. The acknowledgment system receivers can
`communicate acknowledgment messages to the central
`transmitter via either a wire or wireless link. The number of
`acknowledgment system receivers is a function of the trans-
`mitting power of the acknowledgment transmitter associated
`with each of the pagers. The transmitter power of pagers is
`generally low, typically less than one watt, based upon the
`requirement for portability of the pager and the necessity to
`minimize the size of the battery for powering the transmitter.
`Such paging acknowledgment systems are most useful for
`local area “on-site” communications systems in view of the
`power limitations of the transmitters associated with the
`pagers.
`
`US. Pat. No. 5,005,014 describes a wide area paging
`communications
`system for
`efficiently
`transmitting
`acknowledgment signals received from a group of portable
`communications receivers to a central station for ultimate
`distribution to the message originators. The wide area com-
`munications system includes a group of cells, a central
`transmitter station, and a group of remote transmitter sta-
`tions and remote receiver stations. A remote transmitter
`station is centrally located within each cell
`to provide
`message transmissions to a set of portable communications
`receivers within the cell. Likewise, a remote receiver station
`is located in each cell to receive acknowledgment signals
`from the portable communications receivers in response to
`receiving messages. Messages are input into the communi-
`cations system via a paging terminal located at the central
`station and subsequently distributed to the remote transmit-
`ters for communication to the portable communications
`receivers. When a message is received by the intended
`portable communications receiver, it will confirm receipt of
`the message by sending an acknowledgment message that is
`received by at least one of the remote receiver stations and
`forwarded to the central
`transmitter station via a remote
`transmitter station.
`
`US. Pat. No. 4,644,351 describes a communications
`system for transmitting messages via a radio channel from
`one of a group of fixed paging central sites having diiferent
`coverage areas to a set of remote paging units. Each paging
`central site includes a group of base stations that cover a
`relatively large and essentially contiguous geographic area
`and are controlled by a network control processor. Each
`remote paging unit is assigned an unique address and is
`associated with one of the central paging sites. When a
`message for a selected remote paging unit is received at a
`paging central site via a PSTN or another value added
`network (VAN), it is stored and a file is searched to discover
`the location of the selected remote paging unit. The message
`and the address are then transmitted by the paging central
`site located in the radio coverage area most likely to contain
`the selected remote paging unit. When the selected remote
`paging unit receives the message, it stores the message and
`returns a message received acknowledgment to the paging
`central site, which, in turn, deletes the message from its
`storage. The remote paging unit receives and acknowledges
`its messages regardless of the central site radio coverage in
`which the unit is located.
`
`10
`
`15
`
`20
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`4
`Present paging acknowledgment systems require a large
`capital investment for the purchase and installation of equip-
`ment to implement a two—way communications system that
`covers a wide communications area because the number of
`
`acknowledgment receivers (and transmitters) in a paging
`acknowledgment system is a function of the limited trans-
`mitting power of the transmitter associated with each of the
`pagers. Although the paging industry is interested in sup-
`plying a page acknowledgment to subscribers of paging
`services, the cost of implementing the paging acknowledg-
`ment system has discouraged many service providers from
`installing such paging acknowledgment systems.
`Accordingly, there is a need to overcome the limitations
`of the prior art by adapting an existing communications
`network to communicate data between a central location and
`numerous remote sites. There is a further need to adapt an
`existing communications network to deliver the acknowl-
`edgment of a message. This new use of an existing com-
`munications system should have a minimum impact upon
`present communications carried by the system. The present
`invention adapts the existing architecture of a CMR system
`in a efiicient and cost-effective manner to support data
`communications via the CMR system, including the collec-
`tion and reporting of data recorded at remote sites and the
`acknowledgment of a page message.
`
`SUMMARY OF THE INVENTION
`
`The present invention solves the problems of the prior art
`by providing an apparatus and method for communicating
`data via a cellular network control channel of a CMR
`system. Telecommunications service suppliers, including a
`company related to the assignee of this application, Bell-
`South Mobility, have already installed the necessary equip-
`ment to support nationwide communications via CMR net-
`works. The inventors have recognized that the CMR system
`is an existing communications architecture which can be
`adapted in a novel manner to supply either one or two-way
`data communications with minimal impact upon the well
`known voice communications offered by the cellular mobile
`radiotelephone network. The present invention takes advan-
`tage of this installed base of communication equipment by
`using the control channel of the CMR system for data
`communications between a central location and numerous
`remote sites. In this manner, the present invention conserves
`the valuable frequency spectrum allocated for the voice
`channels that support normal telephone conversations on the
`CMR system.
`Briefly described, the present invention is a data message
`system for communicating data collected from remote data
`sources. The data message system includes sets of data
`reporting devices, at
`least one mobile switching center
`(MSC) of a CMR system, and a data collection system
`connected to the MSC. Each data reporting device includes
`a monitor and a cellular communications device. The moni-
`tor, which is connected to a remote data source, monitors the
`operation of the remote data source to obtain selected data.
`The cellular communications device is connected to a cor-
`responding monitor and, in response to selected data, trans-
`mits a data message containing the selected data. The MSC
`receives data messages via a cellular network control chan—
`nel of the CMR system from the cellular communications
`devices operating within coverage areas of the CMR system.
`In turn,
`the MSC sends the data messages to the data
`collection system via a first communications link. The data
`collection system, which is connected to a memory storage
`device, stores each data message and thereafter processes the
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`stored data messages. The data collection system can accept
`data communications that are compatible with EIA/TIA
`Interim Standard 41 (IS—41) or any other vendor proprietary
`protocol.
`The data collection system also can transmit the stored
`data message to a data processing system via a second
`communications link. The data processing system, which
`also operates to store and/or process the contents of the data
`message, is typically located at a site remote from the data
`collection system. This permits processing of selected data
`at a central location that is more convenient for the user,
`rather than conducting such operations at the location for the
`data collection system. Although the data collection system
`and the data processing system are typically located at
`separate sites, the operations of the data collection and the
`data processing system also can be combined or otherwise
`integrated by installing those systems at the same physical
`location.
`
`By use of the present invention, selected data acquired
`from various remote sites can be communicated to a single
`location. The data sources typically include utility meters,
`community antenna television (CATV) pay-per—view (PPV)
`terminals, vending equipment, and security alarm systems.
`The selected data describes certain parameters of operation
`or performance by each of the data sources. For example, if
`the data source is an electrical utility meter located proxi-
`mate to the consumer’s location, then a utility can obtain
`parameters, such as the power demand for a certain time
`interval, recorded by a monitor connected to the source and
`communicated via the control channel of the CMR system.
`More particularly described,
`the monitor includes a
`recorder for recording the selected data during at least one
`predetermined time period. The recorder can add to the
`selected data a time tag indicating the relative time for the
`start of the predetermined time period. The use of the time
`tag permits correlation of the selected data to a specific time,
`thereby assisting processing of the collected data at a later
`date.
`
`The cellular communications device, which can be imple—
`mented as a cellular radiotelephone transceiver, transmits
`the selected data to the MSC in a data-type format via the
`control channel of the CMR system. This conserves the use
`of the frequency spectrum associated with the voice channel
`of the CMR system and avoids interfering with call traffic on
`the voice channel. The data transmission by the cellular
`communications device can be initiated in response to a
`status signal output by the monitor. This status signal
`indicates that the monitor has recorded selected data from
`the data source and, based upon completion of this data
`collection operation, prompts the cellular communications
`device to transmit the stored selected data.
`
`To minimize interference to normal control Operations on
`the control channel,
`the cellular communications device
`typically transmits the selected data during certain off-peak
`times of operation for the CMR system. Specifically, the
`cellular communications device monitors the cellular net—
`work control channel to detect a stream of busy idle bits. The
`status of each of the busy idle bits indicates whether at least
`one cellular source has initiated a cellular communication
`with the MSC via the cellular network control channel
`during a particular time period. A busy idle bit set to the
`binary value of one indicates that the control channel is busy.
`Based upon the status of each of the busy idle bits trans-
`mitted during a selected time period, the cellular commu-
`nications device determines the level of communications
`activity on the cellular network control channel. The cellular
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`communications device transmits the data message to the
`MSC during a “window of opportunity” when the results of
`this monitoring operation indicate that the communications
`on the control channel have been at a level which would
`permit a data transmission on a noninterference basis.
`Alternatively,
`the cellular communications device can
`transmit the data message at a selected time period that
`represents a desirable time for such communications, such
`as the early morning hours when call traffic on the CMR
`system is normally at a low level. The cellular communica-
`tions device includes a clock that outputs a clock signal upon
`expiration of a time interval, which is a time that is typically
`associated with minimal cellular call activity. In response to
`the clock signal, the cellular communications device trans-
`mits a data message containing previously stored selected
`data to the MSC via the cellular network control channel. In
`this manner,
`the cellular communications device can be
`programmed to transmit during off-peak usage times for the
`CMR system, thereby minimizing interference to the control
`operations conducted by the CMR system over the control
`channel.
`The cellular communications device also can conduct
`selected operations in response to receiving command sig-
`nals from the MSC via the cellular network control channel.
`The command signals comprise address data, and each of the
`cellular communications devices is responsive to the com—
`mand signals only for particular address data. The cellular
`communications device transmits a data message to the
`MSC via the cellular network control channel in response to
`receiving a selected command signal. In response to receiv-
`ing another command signal, the cellular communications
`device also outputs an instruction signal to prompt a data
`recording operation by its corresponding monitor. In turn,
`the monitor monitors the operations of the remote data
`source and obtains selected data for a certain monitoring
`time period. Furthermore, the time interval for the clock of
`the cellular communications device also can be set to a
`certain time in response to receiving yet another command
`signal.
`The data message comprises selected data and a prede—
`termined identifying characteristic that uniquely identifies
`the cellular communications device which transmits the data
`message to the MSC. The data message is formatted to
`correspond to an identification signal, often referred to as a
`registration signal, which is normally transmitted by a
`cellular radiotelephone unit when the device first identifies
`itself to the CMR system. The identification signal normally
`comprises separate data fields containing a mobile telephone
`number and an electronic serial number (ESN). Thus, the
`predetermined identifying characteristic is inserted within a
`data field that represents the mobile telephone number and
`the selected data is inserted within a data field that represents
`the ESN. Each cellular communications device is assigned
`a different predetermined identifying characteristic, which
`can be a conventional telephone number, a selected 10 digit
`number, or at least a portion of a mobile telephone number
`[XXX XXXXXXX] that belongs to a set of unassigned
`mobile telephone numbers of the CMR system. Accordingly,
`the selected datais communicated via the control channel of
`the CMR system when the cellular communications device
`first identifies itself or “registers” for operation with the
`MSC.
`'
`
`invention, a paging
`For another aspect of the present
`acknowledgment system is provided for communicating
`both (1) paging messages and (2) acknowledgment mes—
`sages to confirm reception of the paging messages. The
`paging acknowledgment system uses the cellular network
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`5,526,401
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`7
`control channel of the CMR system for communicating an
`acknowledgment message, which verifies receipt of a paging
`message, to an acknowledgment message collection site.
`The paging acknowledgment system includes a commu-
`nications system, a set of remote communications devices,
`and at least one MSC of a CMR system. In response to a
`paging message from a paging party, the communications
`system prepares a data message corresponding to the paging
`message. The data message contains an address
`that
`uniquely identifies a selected remote communications
`device, an acknowledgment code that uniquely identifies the
`corresponding paging message, and paging dataintended for
`communication to a user or subscriber associated with the
`
`selected remote communications device. This acknowledg-
`ment code is stored by the communications system to enable
`the later use of this stored data to support a determination of
`whether the data message has been properly acknowledged
`by the selected remote communications device. The com-
`munications system thereafter transmits the data message
`via a communications network to a selected remote com-
`munications device.
`
`A remote communications device responds to a data
`message containing its particular address by preparing and
`transmitting an acknowledgment message to the MSC via a
`cellular network control channel of the CMR system. The
`acknowledgment message contains the acknowledgment
`code to indicate a valid reception of the data message. As an
`option,
`the acknowledgment message also can contain
`responsive operation data input by the user to respond to the
`paging data or supplied by equipment connected to the
`remote communications unit. The operation data can be
`either manually or automatically input to the remote com-
`munications device for eventual transmission via the CMR
`system.
`The MSC communicates via the cellular network control
`channel with the remote communications devices operating
`within a cell of the CMR system. In response to the
`acknowledgment message,
`the MSC recognizes that
`the
`message is associated with a remote or foreign CMR system.
`Accordingly, the MSC transmits the acknowledgment mes-
`sage to the appropriate remote CMR system, which is
`represented by the communications system. The communi-
`cations system determines that the acknowledgment mes-
`sage contains an acknowledgment code.
`In response to the acknowledgment message, the com—
`munications system processes the acknowledgment message
`and determines “whether the acknowledgment message cor-
`responds to a particular one of the data messages. This
`determination is made by comparing the acknowledgment
`code in the acknowledgment message to the stored