United States Patent [191
`Gutman et a].
`
`[54]
`
`RELIABLE WIRELESS MESSAGE
`DISTRIBUTION SYSTEM
`
`[75]
`
`[73]
`
`[21]
`[22]
`[51]
`[52]
`
`[5 3]
`
`[5 6]
`
`Inventors: Jose Gutman. Boynton Beach; James
`A‘ wright‘ Cor a1 Springs‘ both of Fla’
`
`Assignee: Motorola, Inc.. Schaumburg. 111.
`
`APPL No; 539,891
`
`Filed:
`
`Oct. 6, 1995
`
`6
`Int. CL .................................................... ..: H04Q 7/14-
`Uns
`------------------------------ n 340/825'54’ 455/313’ 370/312
`_
`
`Fleld of Search ....................... .. 340/825.44. 825.54.
`340/825-031 825-47; 455/382- 31-39 371/32-
`33; 37OI346~ 312
`
`,
`References cued
`U_S_ PA'I'ENF DOCUMENTS
`
`5/1986 Burke e‘ "1
`
`4,590,473
`tgggggi
`4:970:714 11/1990 Chen et a1.
`
`340/82544 X
`..................... .. 340/32554
`....................... .. 371/32 X
`
`6/1992 Moore .
`5,124,697
`5,153,582 10/1992 Davis .
`
`USOO5748 100A
`Patent Number:
`Date of Patent:
`
`[11]
`
`[45]
`
`5,748,100
`May 5, 1998
`
`5,168,493 12/1992 Nelson et al- -
`5,245,616
`9/1993 015011 ...................................... .. 371/32
`5,570,367 10/1996 Ayanoglu et a].
`370/346
`
`. _ .
`.
`Primary Exammer Edwin C. Holloway. I11
`[57]
`ABSTRACT
`
`An acknowledge-back selective call system (100) transmits
`a ?rst acknowledge-back page (309) that includes a ?rst
`message data (306) and address information (302) that
`matches a ?rst predetermined address (140) at an
`acknowledge-back selective call transceiver (130) and a
`second acknowledge_back page (300) that includes a s?cond
`
`matches a second predetermined address (142) at the
`acknowlcdge_back selective call tmnsceivm- (13o). Th?
`acknowledge-back selective call transceiver (130) receives
`the second acknowledgerback page (300). and. in response
`thereto. transmits an acknowledge-back con?rmation
`response (500). the acknowledge-back con?rmation
`response (500) including a message reception status infor
`mation (502) indicating a message reception status for the
`?rst acknowledge-back page (300) and a message reception
`status information
`indicating a mcssagc rcocption
`Status f°r thc “00nd ackmwledgc‘back Page (300)‘
`
`1 Claim, 8 Drawing Sheets
`
`AB CENTRAL SYSTEM
`
`113
`4“ CONFIRMATION
`RESPONSE
`TRACKING J
`DATABASE
`
`102
`J
`
`134
`AB SCH J ’
`‘ 148
`
`mmmwmf 124
`a...‘
`‘a
`‘g
`
`mmAQEABEA
`
`\k
`
`132
`\\
`AB sen
`
`116
`
`[112
`
`MESSAGE MEMORY
`
`m \ 1
`CENTRAL SYSTEM J
`CONTROLLER
`1
`1
`114
`m\ ‘V
`' r
`
`OUTPUT ‘- INPUT CONTROLLER CONTROLLER
`
`
`ADDgtESS /
`;’
`‘ 150
`ADDEESS
`1___- ,1
`’
`
`144
`\@
`145
`5
`g
`
`
`
`104
`MESSAGE
`ORIGINATING
`DEVICE
`
`ADDRESS '40
`i,
`I,
`1
`142
`3'95
`ADDRESS /
`‘1.5’
`2
`//
`R.‘
`1:10 "a,
`"”'-...,.....,../M”/
`
`ADDRESS 4
`
`5 I
`
`General Electric Co. 1005 - Page 1
`
`

`
`U.S. Patent
`
`59m.M
`
`8991|.
`
`Sheet 1 of 8
`
`mmmmEn_o<
`
`ommmEn_o<
`
`mo<mmm__2
`
`>mos_m__>_
`
`
`
`s_m:m>m._<Ezmom<
`
`
`
`ZO_._.<_>E_n_ZOO
`
`mmzommmm
`
`oz_v_o<E
`
`mm<mE<o
`
`
`
`s_mFm>m._<Ezmo
`
`mmjompzoo
`
`
`
`._.Dn_._.DO._.Dn_Z_
`
`
`
`mmjomrrzoomm_._._oEzoo
`
`mm<mmm__2
`
`oz:.<z_o_mo
`
`mo_>mo
`
`General Electric Co. 1005 - Page 2
`
`

`
`US. Patent
`
`May s, 1998
`
`Sheet 2 of 8
`
`5,748,100
`
`202
`
`204 K
`
`TRANSCEIVER ‘
`
`} r206
`
`K208
`
`OEOOOER
`
`ENOOOER
`
`K216
`
`SENSIBLE
`AI_ERT
`
`>
`POWER
`OONSERvATION <___ CONTROLLER __> DISPLAY
`
`228\
`
`TIMER 4
`
`A
`
`220 \
`USER INPUT
`
`K214
`
`MESSAGE
`MEMORY
`
`K212
`ADDRESS
`MEMORY
`
`222 \
`
`NON-VOLATILE DATA MEMORY
`
`222
`
`PROGRAM
`MEMORY
`I
`
`\224
`
`PARAMETER
`MEMORY
`I
`
`\226
`1.3Q
`
`FIG. 2
`
`General Electric Co. 1005 - Page 3
`
`

`
`US. Patent
`
`May 5, 1998
`
`Sheet 3 of 8
`
`5,748,100
`
`K302 /. 304
`RESPONSE
`STATUS
`
`ADDRESS
`
`f 306
`
`MESSAGE DATA
`
`Q0_0
`
`AB GROUP 1 MESSAGE 1
`402 f
`GROUP MEMBER
`ADDRESS
`
`K- 404
`r
`ACKNOWLEDGED
`RECEPTION
`
`2
`
`4
`
`6
`
`NO
`
`NO
`
`NO
`
`f 406
`NEXT GROUP
`PAGE TIME
`
`8/31/95 AT 3 AM.
`
`8/31/95 AT 3 AM.
`
`8/31/95 AT 3 AM.
`
`400
`
`General Electric Co. 1005 - Page 4
`
`

`
`US. Patent
`
`May s, 1998
`
`Sheet 4 of 8
`
`5,748,100
`
`r 502
`
`K 504
`
`.
`
`- -
`
`ACKNOWLEDGE
`ADDRESS
`
`PREV'OUS
`- - - ACKNOWLEDGE - - -
`ADDRESS
`
`5(1)
`
`K102
`602
`AB CENTRAL (D ADDRESS MESSAGE _/
`SYSTEM
`1
`‘DATA
`
`@ ADDRESS MESSAGE _534
`2
`DATA
`
`ACK
`@ ADDRESS
`2
`
`4
`
`ACK
`ADDRESS
`1
`
`79'
`
`16’
`
`FIG. 6
`
`> 130\
`AB SCH
`
`> ADDRESS
`1
`ADDRESS
`2
`\
`
`606
`
`General Electric Co. 1005 - Page 5
`
`

`
`US. Patent
`
`May s, 1998
`
`Sheet 5 of 8
`
`5,748,100
`
`704
`
`ANY
`AB MESSAGE
`IN MESSAGE
`MEMORY
`
`706
`
`MESSAGE
`ID# OF CURRENT AB
`MESSAGE IN CONFIRMATION
`RESPONSE
`DATABASE
`
`710 f
`
`NO
`
`INITIALIZE AN AB MESSAGE
`DATABASE FOR CURRENT
`MESSAGE |D#
`
`YES
`
`CURRENT AB
`MESSAGE
`
`\
`GET NEXT AB MESSAGE
`IN MESSAGE MEMORY
`
`716
`
`‘
`
`718 K
`FORMAT AB MESSAGE
`AND COUPLE ADDRESS
`INFoRMATIoN USING AB
`MESSAGE DATABASE
`720
`I r
`,
`SET RESPONSE STATUS
`
`END OF
`AB MESSAGE’S
`IN MESSAGE
`
`YES
`
`722
`I r
`TRANSMIT AB PAGE
`
`FIG. 7
`
`706
`
`706
`
`General Electric Co. 1005 - Page 6
`
`

`
`US. Patent
`
`May s, 1998
`
`Sheet 6 of 8
`
`5,748,100
`
`802
`
`ENTER
`SET REPONSE
`STATUS
`
`SPECIAL
`RESPONSE
`MODE
`
`YES
`
`SET RESPONSE
`STATUS TO NORMAL
`RESPONSE MODE
`
`SET RESPONSE
`STATUS TO SPECIAL
`RESPONSE MODE
`
`810
`
`REQUEST
`RESONSE TO
`A PREVIOUS AB
`MESSAGE
`
`/ 812
`SET RESPONSE STATUS
`TO QUERY STATUS OF A
`PREVIOUS AB MESSAGE ID#
`
`814
`
`EXIT SET
`RESPONSE
`STATUS
`
`General Electric Co. 1005 - Page 7
`
`

`
`US. Patent
`
`May s, 1998
`
`Sheet 7 of 8
`
`5,748,100
`
`902
`
`904
`\ RECEIVE AB PAGE
`I
`
`906
`K
`GET RESPONSE STATUS
`FROM AB PAGE
`
`914 \
`
`PREPARE AB
`CONFIRMATION
`RESPONSE
`
`SPECIAL
`RESPONSE
`MODE
`'?
`
`908
`
`YES
`
`K 910
`
`INHIBIT AB
`CONFIRMATION
`RESPONSE
`
`912
`
`REQUIRE
`RESONSE TO
`A PREVIOUS AB
`MES?SAGE
`
`/ 918
`SET AB CONFIRMATION
`RESPONSE TO INCLUDE
`STATUS OF A PREVIOUS
`AB MESSAGE ID#
`
`920 /
`TRANSMIT AB CONFIRMATION RESPONSE
`
`912
`
`FIG. 9
`
`General Electric Co. 1005 - Page 8
`
`

`
`US. Patent
`
`May s, 1998
`
`Sheet 8 of 8
`
`5,748,100
`
`1 002
`
`1004
`\ RECEIVE AB CONFIRMATION
`RESPONSE
`+
`1006
`\ UPDATE DATABASE FOR
`cuRRENT AB MESSAGE ID#
`
`1 008
`
`PREVIOUS
`AB MESSAGE |D#
`RESPONSE
`?
`
`YES
`
`1010
`
`K.
`UPDATE DATABASE
`FOR PREVIOUS AB
`MESSAGE |D#
`
`FIG. 10
`
`General Electric Co. 1005 - Page 9
`
`

`
`5.748.100
`
`1
`RELIABLE WIRELESS MESSAGE
`DISTRIBUTION SYSTEM
`FIELD OF THE INVENTION
`This invention relates in general to selective call commu
`nications and more speci?cally to a method and apparatus
`for increasing communication throughput and for reducing
`contention among transmissions in a two-way selective call
`system.
`
`15
`
`BACKGROUND OF THE INVENTION
`Contemporary selective call systems. e.g.. paging
`systems. employ messaging schemes that can typically
`deliver voice. numeric. or alphanumeric messages to sub
`scn‘bers. The majority of selective call systems transmit
`address and message information using a communication
`protocol such as Great Britain’s Post Ot?ce Code Standard
`ization Advisory Group. POCSAG. or Motorola’s Golay
`Sequential Code. GSC. More recently. the ReFlertTM proto
`col of Motorola. Inc.. of Schaumburg. 111. allows selective
`call systems to handle two-way communication. e.g..
`acknowledge-back (ack-back) messaging. with portable
`transceivers. such as with the Motorola Tango"M personal
`messaging unit (PMU). or pager. In an ack-back communi
`cation system a central system can send wireless messages
`25
`to a portable transceiver unit such as a PMU. and the PMU
`can send wireless messages to the central system.
`Two-way communication allows a central system to
`verify that a portable transceiver unit (portable unit)
`received a wireless message transmitted by the central
`system and destined for reception by the portable unit A
`con?rmation wireless message. e.g.. an ack-back response
`message. sent from the portable unit back to the central
`system in response to having received a wireless message
`therefrom provides an a?irmative con?rmation back to the
`central system that the wireless message was reliably deliv
`ered and received by the portable unit. This handshake
`messaging. i.e.. sending a con?rmation response message
`back to a central system for each wireless message received
`by a portable unit. can signi?cantly enhance the reliability of
`communication in a selective call system. However. the
`increased number of transmitted messages due to the hand
`shake messaging increases the message communication and
`message processing time delays in the selective call system.
`This added delay tends to reduce the message communica
`tion e?iciency of the selective call system. which may not be
`acceptable under certain operational conditions of the selec
`tive call system. as will be discussed below.
`Under certain operational conditions in the selective call
`system. for example. messaging tra?ic may be high for an
`available message communication throughput capacity for
`the selective call system. Any signi?cant additional message
`tra?ic can detrimentally affect the operational e?iciency of
`system resources. such as limited by a messaging throughput
`capacity of a wireless communication channel. or limited by
`messaging throughput capacity of communication links. or
`limited by an operational e?iciency of central system
`resources such as near-full memory queues or overloading
`of tasks for devices that handle messaging operations. or a
`combination of all of the above communication phenomena.
`Generally. the number of messages that a selective call
`system can handle during peak communication tra?ic peri
`ods constrains the number of total customers that can be
`serviced by the selective call system. The total number of
`customers handled by the selective call system typically
`determines the commercial viability of the selective call
`system.
`
`2
`Furthermore. although conventional ack-back messaging
`can maintain a high level of reliability in message commu
`nication by sending an immediate ack-back message in
`response to every wireless message received by a portable
`unit. under certain messaging conditions transmitting an
`immediate ack-back message response for every wireless
`message received by a portable unit may not be commer
`cially practicable.
`Speci?cally. to enhance the likelihood of commercial
`viability of a selective call system the messaging throughput
`capacity of the selective call system should be as high as
`possible. Normally. a selective call system has a one-way
`messaging throughput capacity that is constrained by the
`maximum number of wireless messages that the central
`system can u'ansmit to the portable units over a unit of time.
`The selective call system also has a two-way messaging
`throughput capacity that is constrained by the maximum
`number of wireless messages that the central system can
`transmit to portable units while the portable units send
`ack-back messages back to the central system in response to
`receiving the wireless messages therefrom over a unit of
`time. For a particular selective call system. the one-way
`messaging throughput capacity is normally higher than the
`two-way messaging throughput capacity. Therefore. to
`enhance the likelihood of commercial viability of a selective
`call system the messaging throughput capacity of the selec
`tive call system should be as high as possible. preferably
`approaching the one-way messaging throughput capacity
`that is higher than the two-way messaging throughput capac
`ity.
`As a ?rst example. under high communication trat?c
`conditions the selective call system’s total messaging
`throughput capacity can be signi?cantly constrained by the
`messaging throughput capacity consumed by the portable
`units sending ack-back response messages to the central
`system. The additional communication tra?ic and process
`ing time delays due to the ack-back response messages may
`reduce the total number of wireless messages that can be
`delivered by the selective call system during the high
`. communication tra?ic conditions.
`As a second example. the central system may transmit a
`multi-recipient ack-back wireless message (a group page)
`destined for a large group of recipient portable units. This
`may be the case while providing information services to
`subscribers of the selective call system. or while providing
`data updates to members of ack-back groups in the selective
`call system. or generally while providing wireless messages
`to members of ack-back groups in the selective call system.
`In response to receiving the group page. recipient portable
`units would transmit back to the central system their ack
`back response messages to con?rm a message reception
`status for the group page. The large number of ack-back
`response messages that the selective call system would have
`to handle over a relatively short amount of time could
`severely reduce. if not totally bottleneck. the wireless mes
`saging throughput of the selective call system. Such a
`reduction in the wireless messaging throughput would create
`signi?cant message communication delays in the selective
`call system. Typically. this condition would not be accept
`able to customers of the selective call system thereby
`detrimentally affecting the commercial viability of the selec
`tive call system.
`Thus. what is needed is a method and apparatus. in an
`acknowledge-back selective call system. for increasing the
`reliability of communication under the varying message
`communication tra?ic loads and the two-way messaging
`communication requirements of the acknowledge-back
`selective call system.
`
`10
`
`20
`
`35
`
`45
`
`50
`
`65
`
`General Electric Co. 1005 - Page 10
`
`

`
`5,748, 100
`
`3
`BRIEF DESCRIPTION OF rrna DRAWINGS
`
`FIG. 1 illustrates an acknowledge-back selective call
`system in accordance with the present invention.
`FIG. 2 illustrates an acknowledge-back selective call
`transceiver in accordance with the present invention.
`FIG. 3 is a protocol diagram illustrating an acknowledge
`back page in accordance with the present invention.
`FIG. 4 illustrates an exemplary acknowledge-back mes—
`sage database for use with an acknowledge-back central
`system of FIG. 1. in accordance with a preferred embodi
`ment of the present invention.
`FIG. Sis a protocol diagram illustrating an acknowledge
`back con?rmation response in accordance with the preferred
`embodiment of the present invention.
`FIG. 6 is a messaging block diagram illustrating an
`exemplary messaging sequence between an acknowledge
`back central system and an acknowledge-back selective call
`transceiver in accordance with the preferred embodiment of
`the present invention.
`FIGS. 7 and 8 are ?ow diagrams illustrating a ?rst
`operational sequence for the acknowledge-back central sys
`tem of FIG. 1 in accordance with the preferred embodiment
`of the present invention.
`FIG. 9 is a ?ow diagram illustrating an operational
`sequence for an acknowledge-back selective call transceiver
`of FIG. 2 in accordance with the preferred embodiment of
`the present invention.
`FIG. 10 is a ?ow diagram illustrating a second operational
`sequence for the acknowledge-back central system of FIG.
`1 in accordance with the preferred embodiment of the
`present invention.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENT
`Referring to FIG. 1. an acknowledge-back selective call
`system 100 (hereinafter. selective call system) delivers
`acknowledge-back pages to subscribers thereof. according
`to the preferred embodiment of the present invention.
`Preferably. the selective call system 100 utilizes the
`Motorola ReFleirTM communication protocol to deliver mes
`sages to and from subscribers of the selective call system
`100. The ReFlex protocol is more fully described in the
`following US. Pat. applications assigned to the assignee of
`the present invention: Ser. No. 08/ 131.243 entitled “Method
`and Apparatus for Identifying a Transmitter in a Radio
`Communication System” ?led Oct. 4. 1993 by Simpson et
`al.; US. Pat. Ser. No. 08/398274 entitled “Method and
`Apparatus for Optimizing Receiver Synchronization in a
`Radio Communication System” ?led Mar. 3. 1995 by Ayerst.
`et al.; US. Pat. Ser. No. 081404.698 entitled “Method and
`Apparatus for Improved Message Reception at a Fixed
`System Receiver” ?led Mar. 15. 1995 by Ayerst et al.; US.
`Pat. Sm‘. No. 08/498212 entitled "Forward Channel Proto
`col to Enable Reverse Channel Aloha Transmissions” ?led
`Jul. 5. 1995 by Ayerst et al.; and US Pat. Ser. No.
`08/502399 entitled “A System and Method for Allocating
`Frequency Channels in a Two~way Messaging Network”
`?led Jul. 14. 1995 by Wang et al.. which are hereby
`incorporated by reference herein. However. any conven
`tional wireless communication protocol that supports two
`way paging communication can be utilized by the selective
`call system 100.
`Speci?cally. an acknowledge-back central system 102
`(hereinafter. central system 102) is coupled to at least one
`message originating device 104. such as via a public
`
`20
`
`25
`
`30
`
`35
`
`50
`
`55
`
`65
`
`4
`switched telephone network 106 (PSTN). The message
`originating device 104 comprises. for example. a telephonic
`entry device that utilizes dual tone multi-frequency (DTMF)
`signaling. or a computing device and modern arrangement
`utilizing modem signaling. or a page entry terminal device.
`or other message originating device that can be coupled via
`a telephone network. Further. a message originating device
`104 that comprises a computing device can couple to the
`central system 102 via other network interfaces. such as via
`an Internet network interface. via an ethernet network
`interface. or via other high speed network interface. or even
`via a dedicated line interface between the message originat
`ing device 104 and the central system 102. Furthermore. a
`message originating device 104 that comprises a wireless
`network interface can couple to the central system 102 via
`a wireless network. such as an infrared communication
`network or a terrestrial or satellite-based radio frequency
`(RF) communication network.
`An input controller 108 comprises a network interface for
`the central system 102 compatible with the type of network
`being used to couple messages from a message originating
`device 104. For example. the input controller 108 comprises
`a telephone interface to couple messages via the PSTN 106.
`A central system controller 110 controls the acknowledge
`back paging function of the central system 102. The central
`system controller 110 is coupled to the input controller 108
`for receiving messages associated with acknowledge-back
`page requests. such as that originated from the message
`originating device 104.
`The central system controller 110 is coupled to a message
`memory 112 for storing acknowledge-back messages and
`associated information. The message memory 112 is pref
`erably a non-volatile memory. The central system controller
`110 is also coupled to an output controller 114 for transmit
`ting outbound aclmowledge-back pages containing mes
`sages or information for subscribers of the central system
`102.
`The central system controller 110 is also coupled to a
`timer 116 for keeping track of time and date information for
`the central system 102. The central system controller 110
`can utilize the time and date information provided by the
`timer 116. for example, for scheduling transmission of
`acknowledge-back pages at predetermined times. as will be
`more fully discussed below.
`The central system controller 110 is coupled to a con?r
`mation response tracking database memory 118. The con
`?rmation response tracking database memory 118 is utilized
`by the central system 102 to keep track of acknowledge
`back paging status for subscribers of the selective call
`system 100. as will be more fully discussed below.
`The output controller 114 is coupled via a communication
`link 120 to at least one acknowledge-back transceiver or
`selective call transceiver base station 122 (hereinafter. base
`station 122) that is typically located in a prede?ned coverage
`area 124. The coverage area 124 comprises a region. such as
`a geographical region. for conducting wireless message
`communication between the base station 122 and the at least
`one ack-back capable selective call transceiver 130 (pager).
`The selective call system 100 typically comprises a plurality
`of prede?ned coverage areas that cover. for example. a wide
`geographical territory.
`The communication link 120 can comprise a direct wire
`line communication link. a modem communication link such
`as over a telephone network. a satellite communication link.
`an RF communication link. or other contemporary commu
`nication linking means. or a combination of the aforemen
`
`General Electric Co. 1005 - Page 11
`
`

`
`5.748.100
`
`15
`
`20
`
`25
`
`35
`
`5
`tioned communication links. The base station 12 operates
`to transmit an outbound acknowledge-back page 126
`(hereinafter. page 126) to at least one acknowledge-back
`selective call transceiver 130 (hereinafter. selective call
`transceiver 130) located within the coverage area 124.
`Further. the base station 122 receives an inbound
`acknowledge-back con?rmation response. or ack-back
`response. 128 transmitted by the at least one selective call
`transceiver 130. The base station 122 forwards the ack-back
`response 128. via the communication link 120. to the output
`controller 114 of the central system 102. In this way. the
`central system 102 transmits a page 126 to the at least one
`selective call transceiver 130. and then receives an ack-back
`response 128 therefrom to con?rm a message reception
`status of the page 126 for the at least one selective call
`transceiver 130. This two-way paging communication
`between the central system 102 and the at least one selective
`call transceiver 130 provides a?irmative con?rmation to the
`central system 102 that page 126 transmitted to the at least
`one selective call transceiver 130 was successfully received
`thereby. This message con?rmation mechanism increases
`the overall reliability of a message delivery system because
`it allows the selective call system 100 to re-transmit a
`message to the selective call transceiver 130 until the
`selective call n'ansceiver 130 acknowledges that the message
`was successfully received by the selective call transceiver
`130.
`The hardware of the central system controller 110 pref
`erably includes a Wireless Messaging Gateway (WMGTM)
`Administrator lm paging terminal. a RF-Conductor!TM mes
`sage distributor, and a RF-Usherl'm multiplexer. manufac
`tured by Motorola. Inc. The controller has software elements
`and preferably runs under a UNIX operating system. The
`software elements are modi?ed in accordance with the
`present invention. The hardware of the base station 122
`preferably includes a Nucleus® OrchestralTM transmitter
`and a RF-Audience!TM receiver. manufactured by Motorola.
`Inc. A more detailed description of the hardware of the
`central system controller 110 and of the base station 122 is
`described in “Introduction to The Wireless Concertl". pub
`lished 1995 by Motorola. Inc.. which is available for sale to
`the public as part No. 6880491G01 from Motorola. Inc.. Ft.
`Worth. Tex.. and which is hereby incorporated by reference
`herein.
`The operation of the selective call transceiver 130 is
`described more fully in U.S. Pat. No. 5.124.697 entitled
`“Aclmowledge Back Pager” issued Jun. 23. 1992 to Moore;
`U.S. Pat. No. 5.153.582 entitled “Method and Apparatus for
`Acknowledging and Answering a Paging Signal” issued Oct.
`6. 1992 to Davis; and U.S. Pat. No. 4.875.038 entitled
`“Frequency Division Multiplexed Acknowledge Back Pag
`ing System” issued Oct. 17. 1989 to Siwiak et al.. which are
`assigned to the assignee of the present invention and which
`are hereby incorporated by reference herein. The ack-back
`capable selective call transceiver 130 is preferably a
`Motorola Tangom pager modi?ed to perform the operations
`described hereinafter. The Tango pager is compatible with
`the ReFlex protocol. The Tango pager is described more
`fully in the Motorola Product Family 255 Service Manual
`published 1995 by Motorola. Inc.. and in the Motorola
`Product Family 255 Series Controller Supplement. pub
`lished 1995 by Motorola. Inc.. which are available for sale
`to the public from Motorola Paging Products Group. Boyn
`ton Beach. Fla. as part No. 6881024B80 and part No.
`68881104B36. respectively. and which are hereby incorpo
`rated by reference herein. A software element. residing in
`non-volatile memory. preferably read-only memory (ROM).
`
`6
`of selective call transceiver 130 is modi?ed to operate the
`microprocessor. preferably a Motorola M68HC1lPl-I8.
`within the pager in accordance with the invention. A person
`skilled in the art of programming modi?es the software
`using a Motorola HCll Reference Manual. published 1991
`by Motorola. Inc.. and using a Motorola MC68HC11PH8
`Technical Data. published 1995 by Motorola. Inc.. which are
`available for sale to the public from Motorola. Inc.. Phoenix.
`Ariz.
`An selective call transceiver 130 may not reliably receive
`the page 126. or may even miss the page 126. because of
`certain communication conditions related to the selective
`call system 100. For example. a selective call transceiver
`132 can be located at a fringe region of the coverage area
`124 where certain wireless communication phenomena such
`as noise interference and other interference signals can
`detrimentally a?ect the reliable reception of pages. A selec
`tive call transceiver 134 can be located. as a second example.
`outside of the coverage area 124 consequently not being
`capable of receiving pages 126. Furthermore. the selective
`call transceiver 130. even if located within the coverage area
`124. can miss reception of a transmitted page 126. For
`example. a physical blocking structure. e.g.. a steel beam
`structure in a building or other similar RF blocking structure.
`can be located within the coverage area 124 interposed
`between the base station 122 and the selective call trans
`ceiver 130 thereby preventing a transmitted signal compris
`ing page 126 from reaching the selective call transceiver
`130. Additionally. the power of the selective call transceiver
`130 can have been turned off at the time when the signal
`comprising the page 126 was transmitted by the base station
`122. Consequently. the selective call transceiver 130 would
`not receive the transmitted page 126 from the base station
`122.
`Under certain communication conditions. it can be unde
`sirable for the at least one selective call transceiver 130 to
`transmit the ack-back response 128 to the central system
`102. For example. under high message communication
`traffic conditions. such as can exist from time to time in the
`coverage area 124 or in the communication link 120. the
`acknowledge-back message communication throughput
`capacity of the selective call system 100 can severely limit
`the number of additional wireless pages 126 (Le. a single
`recipient acknowledge-back page) that can be handled by
`the selective call system 100. The additional message com
`munication and processing time required to transmit ack
`back responses 128 to the central system 102 for the pages
`126 that were received by the at least one selective call
`transceiver 130 consume the available message communi
`cation throughput capacity. This available message commu
`nication throughput capacity could be alternatively better
`utilized to transmit additional wireless pages 126 without
`immediately transmitting the ack-back responses 128 there
`for to help improve the overall wireless message commu
`nication throughput of the selective all system 100. such as
`during peak message communication tra?ic conditions.
`As a second exemplary communication condition. a
`multi-recipient acknowledge-back page (hereinafter. group
`page) is transmitted by the selective call system 100 for
`reception by a large group of selective call transceivers 130.
`132. 134. The selective call system 100 broadcasts. via at
`least one multi-recipient page. many different types of
`information to subscribers of the selective call system 100.
`For example. the selective call system 100 can broadcast
`information services such as news. weather. sports. ?nancial
`information and other useful information to subscribers of
`the selective call system 100. The selective call system 100.
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`as a second example. can broadcast at least a portion of a
`software program for delivering software updates. via at
`least one group page. to subscribers of the selective call
`system 100 and to the software update service. As a third
`example. the selective call system 100 can broadcast. via at
`least one group page. group messages to members of the
`group. such as a work group. or a group of family members
`or friends.
`A transmission of a group page to a large group of
`selective call transceivers 130. 132. 134. such as discussed
`above. can result in signi?cantly increased message com
`munication traf?c and a long processing delay to acknowl
`edge reception of the group page from the members of the
`large group of selective call transceivers 130. 132. 134. The
`increased message communication tra?ic and the long pro
`cessing delay can bottle-neck message communication traf
`?c in the selective call system 100. This bottle-neck condi
`tion and the associated communication delays can severely
`inconvenience subscribers of the selective call system 100.
`The selective call system 100 can improve the overall
`mes sage communication throughput and avoid a bottle-neck
`condition by. for example. temporarily inhibiting the wire
`less transrnission of the ack-back responses 128 from the
`large group of selective call transceivers 130. 132. 134. until
`a later time and while maintaining reliable wireless message
`communication for the group page. as will be more fully
`discussed below.
`In summary. under a number of acknowledge-back paging
`conditions. as discussed above. it can be undesirable. and
`even unnecessary. for the at least one selective call trans
`ceiver 130 to immediately transmit back to the central
`system 102 a con?rmation via the ack-back response 128. It
`can be more advantageous for the ack-back response 128 to
`be transmitted at a later time. and under di?erent message
`tra?ic conditions. as will be more fully discussed below.
`The at least one selective call transceiver 130 can be
`selectively addressed by the selective call system 100 by
`transmitting a page 126 that comprises address information
`that matches predetermined address information at the at
`least one selective call transceiver 130. For example. the at
`least one selective call transceiver 130 comprises an address
`memory that contains a ?rst predetermined address infor
`mation 140 and a second predetermined address information
`142. The selective call transceivers 130. 132. 134. in the
`selective call system 100 likewise can be con?gured with
`predetermined address information to be selectively addres
`sable by more than one address in the selective call system
`100.
`For example. the second selective call transceiver 132
`comprises a ?rst predetermined address 144. i.e.. with an
`exemplary address value of 3. and a second predetermined
`address 146. Le. with an exemplary address value of 4.
`Additionally. a third selective call transceiver 134 comprises
`a third predetermined address 148. with an exemplary
`address value of S. and a second predetermined address 150.
`with an exemplary address value of 6. The selective call
`transceivers 130. 132. 134. individually comprising a plu
`rality of predetermined addresses can each be selectively
`addressed by the selective call system 100 transmitting a
`page 126 comprising address information that matches at
`least one of the plurality of predetermined addresses of the
`selective call transceivers 130. 132. 134.
`The at least one selective call transceiver 130. for
`example. is con?gured to be individually selected by a page
`126 comprising address information that matches a second
`predetermined address information 142 at the selective call
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`8
`transceiver 130. Further. the at least one selective call
`transceiver 130 can be a member of a large group of
`selective call transceivers 130. 132. 134. that is selectively
`addressable by a group address that matches the ?rst pre
`determined address information 140 of the at least one
`selective call transceiver 130. This group addressing scheme
`will be more fully discussed below.
`An addressing scheme for an acknowledge-back group
`can utilize a common predetermined address information for
`each of the members of the acknowledge-back group. For
`example. the ?rst predetermined address 140 at the at least
`one selective call transceiver 130. and the ?rst predeter
`mi