I|||||I|||||l|IllIlllllllllIlllllllllllllllllll|||||||||I||||||||||l|llll||
`US005566236A
`5,566,236
`[11] Patent Number:
`[19]
`United States Patent
`9
`MeLam et al.
`[45] Date of Patent:
`Oct. 15 1996
`
`
`[54] SYSTEM AND NIETHOD FOR
`RE-ESTABLISHING A DISCONNECTED
`TELEPHONE COMMUNICATION
`
`Inventors: Patrick J. MeLampy, Beverly;
`Andrew D or
`Semen/i116 both of
`M
`'
`’
`y’
`
`ass.
`,
`_
`_
`[731 ASSlgneeI Pilority Call Management, Inc-y
`Wlhmngtona M355.
`
`[21] Appl' NO': 583’673
`[22] Filed:
`Jan. 5, 1996
`
`Related US. Application Data
`
`4,783,796 11/1988 Ladd ......................................... 379/67
`4,887,265 12/1989 Felix .. ... . ...,..
`. . ... 379/59
`
`. .. ... ..
`... .. 379/67
`4,926,462
`5/1990 Ladd et a1.
`
`6/1990 Hellwarth et a1.
`4,935,956
`379/112
`
`
`379/112
`......
`4,972,464 11/1990 Webb 61 a],
`5,090,050
`2/1992 Heifer-nan .......................... 379/60
`5/1992 Richardson, Jr. et al.
`5,113,430
`379/88
`
`..................
`5,140,626
`8/1992 Ory et a1.
`379/201
`5,199,062
`3/1993 Von Meister et a1.
`379/67
`
`.......
`..... 379/37
`5,235,630
`3/1993 Moody et a1.
`
`5,280,541
`1/1994 Marko et a1.
`379/61
`
`.... . .
`5,375,161
`12/1994 Fuller et al.
`. . . .. 379/57
`
`Primary Examiner—Krista M. Zele
`Assistant Examiner—Scott Wolinsky
`Attorney, Agent, or Firm—Adam H. Tachner; Crosby,
`Heafey, Roach & May
`
`[63] Continuation ofSer. No. 198,032, Feb. 16, 1994, abandoned.
`
`[57]
`
`ABSTRACT
`
`Int. C1.6 .................................................... .. H04M 3/42
`[51]
`[52] US. Cl.
`............................ .. 379/201; 379/58; 379/63;
`379/67; 379,242; 379/207
`[58] Field of Search ............................. .. 379/201 207
`379/219’ 220, 229’ 230, 245’ 246, 127’
`142’ 60’ 59, 88, 213, 265, 211’ 154’ 57’
`61 63 67 242 58
`’
`’
`’
`’
`
`[56]
`
`References Cited
`
`4,685,127
`4,757,526
`
`U.S. PATENT DOCUMENTS
`8/1987 Miller et a1.
`.......................... .. 379/221
`7/1988 Foster et a1.
`.......................... .. 379/201
`
`A system and method provides a tandem switch and call
`control/management Platform to establish a telephone 00n-
`nection (bridge) between two parties, the telephone connec—
`‘10“ being initiated by One of the Panies- “"3 tandem Switch
`connects a telecommunications system (Centrex or PBX)
`with cellular or wireless telephones. If either party is dis-
`connected from the tandem switch, the telephone connection
`between the tandem switch and the remaining party is
`maintained. The telephone connection is re-established by
`instructing the tandem switch to reconnect the disconnected
`party to the maintained party.
`
`40 Claims, 4 Drawing Sheets
`
`‘
`
`CUSTOM PREMISE
`
`CELLULAR
`PHONE
`
`37
`
`CELLULAR
`SWITCHING
`
`NETWORK
`
`40
`
`27
`
`28
`
`25
`
`33
`
`DESKTOP
`
`PHONE
`
`— voxcem
`
`‘_—\
`CENTRAL H
`
`OFFICE
`;
`SWITCH
`I
`
`RECEPTIONIST
`
`SECRETARY
`
`
`
`ll.
`
`32
`
`
`
`34
`
`35
`
`PROCESSING
`
`
`ELEMENTS
`
`
`
`CALLER
`
`L—-——-____-—_ _——-—A
`
`PCS PLATFORM
`
`3|
`
`000001
`
`|PR2016-01258
`
`YMAX CORP. V. FOCAL IP
`
`YMAX EXHIBIT 1029
`
`000001
`
`YMAX EXHIBIT 1029
`YMAX CORP. V. FOCAL IP
`IPR2016-01258
`
`

`

`US. Patent
`
`Oct. 15, 1996
`
`Sheet 1 of 4
`
`5,566,236
`
`mkmwozs...mummaul—D...onEm
`
`wmzoxm
`
`mom82m
`
`582d
`
`
`
`
`
`ImmzoxmxmfizmumoEo.3528
`
`_ .
`
`OE
`
`(En...
`
`m_
`
`El
`
`mu?
`
`382dmomzoEEE
`
`N.mxmn.
`
`
`rmmt.oziotam
`
`
`
`Wu»...x5352motto.558
`
`mzozmxmn.
`
`Im$29.96Exmosfiz
`Eloziotsm
`
`mmEmEmezmo
`
`
`
`
`
`wpumozg83%.;nmadmmmkzx102,ka
`
`mum
`
`__o.mmI\/.\
`
`mmmufim—B
`
`mmmjmmts
`
`
`
`mzormwumt.mum:02m
`
`mmEOPmDU
`
`
`
`022.2memmimmm
`
`Swim...an
`
`\_/\_/
`
`
`
`mo_>mmm\mu_mmo44m...sz
`
`
`
`.rzmSESOmmmoSOmn.
`
`\_/
`
`/.\
`
`5.32.150
`
`OZ_IU.C>>m
`
`xmoz’kmz
`
`000002
`
`000002
`
`
`
`
`

`

`M
`
`2.,mm6.65889:.
`s,NE5,
`
`EmommuummmEmuzuumx
`
`U
`
`
`on”ozfiwmoowavm
`mu_o>m.SQ
`
`tsmmfigt555E50:
`
`.1V5558.:m.mofimmhz.%.mamHm2:ca0g:8«mmzofiomzzoom6SEE»;Ebmanuz:2mmH,A5882: S8own;
`_ISWEo25%M_mm»_3mmE<o<aN:28quovEzmuzfi1.a2EEE13ma8wBEES.mEnEm$-23.
`.
`SEE»!m0x5.Im2:5350mzoEzeoummnozzomutaBEES.mmIEm2:N20:26
`.ESMLOQJaF52
`
`yam—Pd:
`
`000003
`
`
`

`

`
`
`US. Patent
`
`Oct. 15, 1996
`
`Sheet 3 of 4
`
`5,566,236
`
`.vm
`
`mm
`
`.mOwaME
`
`MZOIn.
`
`:—_<S_mo_O>
`
`mmFm_zo_Emomm
`
`>m<kmm0mm
`
`mm
`
`mm
`
`mOE
`
`
`
`mwgmmn.Egmao
`
`«3:54:50
`
`Oz_IU.:>>m
`
`ququu
`
`mzorm
`
`Admkzmo xmogkmz
`
`MUEuO
`
`IO._._>>m
`
`mm
`
`000004
`
`OZGWMUONE
`
`WPZMEMJM
`
`mo_O>
`
`mo_m._.DO
`
`«@1de
`
`
`
`000004
`
`
`
`
`

`

`
`
`US. Patent
`
`Oct. 15, 1996
`
`Sheet 4 of 4
`
`5,566,236
`
`vOE
`
`SmozaF
`
`IU._._>>w
`
`mom
`
`oz_mmmoomm
`
`mp.szme
`
`MU_O>
`
`mo_m.50
`
`mun—Ado
`
`Vm
`
`mm
`
`mOFxmwo
`
`mZOIm
`
`n__<2mo_o>
`
`mmPQZOEhmumm
`
`rmdmeUmm
`
`mm
`
`NM
`
`lamp.sz
`
`onmo
`
`Iot>>m
`
`Ov
`
`mu_>mwm
`
`JOEZOU
`
`moSmmm
`
`F2_On_
`
`000005
`
`
`
`mmimmn.5.0.530
`
`«.44DJIGU
`
`OZ_IU.:>>m
`
`5.52,sz
`
`deDujmo
`
`MZOIm
`
`
`
`000005
`
`
`
`
`
`
`

`

`
`
`1
`SYSTEM AND METHOD FOR
`RE-ESTABLISHING A DISCONNECTED
`TELEPHONE COMMUNICATION
`
`This is a continuation of application Ser. No. 08/198,032
`filed on Feb. 16, 1994, now abandoned.
`
`FIELD OF THE INVENTION
`
`The present invention relates in general to telecommuni—
`cations equipment, and more particularly relates to methods
`and apparatus for interfacing wireless telecommunications
`terminals into an existing telecommunications network.
`
`BACKGROUND OF THE INVENTION
`
`The telecommunications industry is currently undergoing
`a massive shift from wired telecommunications devices to
`wireless devices. The impetus for this transition is mobility,
`and reduced cost for system reconfiguration. The invention
`described herein fits the form and function of a “Personal
`Communications Services” as described in industry terms.
`Cellular and other wireless telephones offer mobility, but
`at the expense of reliability, and interoperability. Addition-
`ally, wireless handsets provide unlimited access to the
`canier of the telephone and lacks a mechanism for incor—
`porating standard call coverage tools which are provided by
`the land based telecommunications systems (PBX or Cen-
`trex).
`Unreliable Connections
`
`Cellular and wireless handsets often lose connection. This
`is due to many technical reasons, including improper hand-
`off between cells, signals below minimum thresholds, loss of
`battery power, etc. Typically, upon a lost connection, the
`caller and wireless user must re-establish communication
`manually.
`Limited Access Screen
`
`Most business telephone extensions are part of the orga-
`nization’s coverage plan. This coverage plan may include,
`but is not limited to, live operator support, secretary or
`co-worker coverage, voicemail, etc. Most business phones
`have buttons for “Do Not Disturb”, and many have display
`screens to identify the (internal) calling party’s number and
`name, if available. Many executives have all arriving calls
`screened by their secretary, limiting direct access to the
`executive only for important calls.
`The rapid growth in wireless device availability compli-
`cates the picture. Cellular telephones are not integrated with
`any organization’s telephone system, as the service is only
`sold and operated from off-premise locations reached via
`Central Office connections. A few other wireless devices
`have recently been made available to the Customer Premise
`Equipment marketplace to provide on-premise, wireless
`handset capability. These newer devices provide only simple
`analog interfaces, with a limited set of capabilities. Some
`manufacturers olfer different levels of integration, but none
`provide direct determination of unknown callers, and the
`ability to “act on” the calls.
`
`The lack of integration of wired and wireless telephones
`means that, for a cellular or cordless user:
`
`No information about who is calling is transmitted to the
`handset.
`
`There is no ability to screen the caller without answering.
`Some wireless devices may be incapable of the “transfer”
`feature to move the call to another terminal.
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`60
`
`65
`
`5,566,236
`
`2
`
`Some wireless devices may not be capable of forwarding
`from the handset to another dialed number.
`Calls can’t be forwarded or transferred from the on-
`premise networks to an elf premise wireless devices
`phone.
`The next generation devices, now just reaching the mar-
`ket, include “wireless Centrex" offerings, which use SS7
`Common Channel Signaling protocols to integrate Centrex
`telephones into a Centrex partition. These services are not
`commonly available due to the slow deployment of the SS7
`overlay signalling network into central offices.
`Handofi/Transfer Between Cellular and Wired Tele-
`phones is Impossible
`When a call arrives on a wireless device, the user of the
`device has the mobility to move from place to place.
`However, because wireless devices are not “secure”, and the
`quality of the voice may be less than that of a wired
`telephone,
`it may be desirable to switch the call
`to the
`nearest wired telephone, but only without losing connection.
`This has the added effect of saving money, since many
`wireless service providers charge for all air time.
`The current art supports automatic handoif between dif-
`ferent wireless systems which are homogeneous and support
`the cellular telephone protocol IS-41 (“roaming”). Unfortu—
`nately, handoffs to wired, or dissimilar wireless networks
`currently was impossible until the development of the cur-
`rent apparatus.
`
`SUMMARY OF THE INVENTION
`
`This invention uses a tandem switch to provide a “bridge”
`between two callers. In a preferred embodiment, the switch
`connects an organization’s
`telecommunications
`system
`(Centrex or PBX), and the cellular or wireless telephones.
`The switch facilitates a call coverage plan for an organiza—
`tion, and provides the ability to seize and dial a plurality of
`wireless networks as needed. An arriving call never totally
`leaves the fabric of the organization’s telecommunications
`system, providing access to all telecommunications cover-
`7
`age options, including transferring to additional parties
`voicemail, etc.
`
`Calls arriving or leaving an organization’s telecommuni-
`cations system which connect to any wireless device can be
`routed to the PCS system described herein. When routed to
`and or through the PCS system, control of the call
`is
`obtained. This control includes the ability to treat each leg of
`the call as independent. The control of the call is used to
`implement the features described below.
`The methods of interconnecting to the on-premise tele-
`communications equipment vary depending on the age and
`technical features of the equipment utilized. In a basic,
`preferred embodiment, the PCS actually holds both legs of
`the telephone calls across its call switching mechanism. The
`PCS will then have separate control over both legs, includ-
`ing the ability to detect near—end or far-end call release,
`rerouting of calls, and preemptive call
`interruption, call
`conferencing, and call joining.
`is
`the call control
`In a more advanced embodiment,
`obtained and trunk and route optimization is performed
`using the Advanced Intelligent Network architecture
`described in the CCITT Recommendations and Bellcore
`documents listed below:
`
`CCITT Q.700: Introduction to CCITT SS7
`
`CCITI‘ Q.775: Guidelines for Using Transaction Capa-
`bilities
`
`CCITT Q.724: Signaling Procedures
`
`000006
`
`
`
`000006
`
`

`

`
`
`5,566,236
`
`3
`
`CCI'IT Q.761: Functional Description of the ISDN User
`Part of SS7
`
`TR-NW I—000246 Issue 2, Revision 2: Bell Communica—
`tions Research Specification of Signaling System Num—
`ber 7
`
`5
`
`SR-NPL-001509 Issue 1: Advanced Intelligent Network
`Release 1 Proposal
`SR-NPL-001623 Issue 1: Advance Intelligent Network
`Release 1 Network and Operations Plan
`The control of the call is retained through the use of
`“triggers” which are set for both arriving calls, and calls in
`progress. The “triggers” fire when certain events occur, and
`control of the call is returned to the PCS system.
`CellGuard
`
`This invention provides a connection safe guard by wait-
`ing for a disconnect to occur on either the caller side, and/or
`the wireless users side. If the wireless user disconnects first,
`then this trigger event will return control of the remaining
`caller to a voice processing system. The voice processing
`system will optionally prompt the caller to indicate whether
`reconnection is desired. If so, the voice processing system
`will re-initiate the call to the wireless device, and/or wait for
`the caller to call back.
`
`If the call originated on a wireless device, and the wireless
`device disconnects, then the remaining caller is prompted to
`see if reconnection is desired. If so, the caller is placed on
`hold, waiting for the wireless device to call back. Optionally,
`an alert is transmitted which could be a page message or
`cellular data message sent to the wireless user to notify of
`the disconnected caller waiting for reconnection.
`If the wireless device address (location and/or dialed
`number) is not known then the caller can be placed on hold,
`awaiting the wireless handset’s reconnection attempt. This
`permits the invention to operate correctly on all wireless
`devices, including those which have no common signaling
`with the PCS.
`This above invention will be called “CellGuard” through-
`out the following document. This invention is not limited to
`cellular or wireless telephones, and will provide the same
`functionality on all types of telecommunications equipment.
`Additionally, the features can be provided using different
`technologies. Illustrative methods of embodying this inven-
`tion are described herein.
`CellScreen
`
`The objective of the invention is to provide call screening
`through multiple means so that the wireless user can deter-
`mine who is calling,
`the nature of the call, etc. before
`speaking to the caller. The unwanted screened call can be
`rerouted, placed into a call coverage option (including
`voicemail), terminated, or handled any way desired by the
`on-premise telecommunications system and selected by the
`user. Throughout this document, the term “CellScreen” will
`be used to describe this embodiment.
`CellSaver
`The hand-off from wireless to wired and vice-versa can be
`performed using the invention described in this document.
`This hand-off can occur once, or several times during the
`course of a single connection. The hand-off is completed by
`having a new call “steal” the call away from the conversa-
`tion in progress. This provides the mechanism for unlimited
`hand-offs between dissimilar networks.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`FIG. 1 illustrates a functional block diagram of the
`claimed system.
`
`10
`
`15
`
`25
`
`3O
`
`35
`
`4O
`
`45
`
`50
`
`55
`
`6O
`
`65
`
`4
`FIG. 2 illustrates a detailed block diagram of the PCS
`system. .
`FIG. 3 illustrates a block diagram of making a connection
`for a cellular subscriber using one embodiment of the
`invention.
`
`FIG. 4 illustrates a block diagram of making a connection
`for a cellular subscriber using a second embodiment of the
`invention including an Advanced Intelligent Network.
`
`DESCRIPTION OF THE PREFERRED
`EMBODIMENTS
`
`The basic device used for implementing the present
`invention is a tandem switch. This tandem switch allows
`connection between one of a variety of lines on one side of
`the switch and one of a variety of lines on the other side of
`the switch. By controlling which lines are connected and
`what lines are held, plus controlling how either line connects
`with other oflice services, the tandem switch can provide a
`wide variety of useful functions that are not currently
`available.
`
`Referring to FIG. 1, this diagram shows the identity and
`connectivity of various
`functional units. Each block
`describes a functional unit. Cellular switching network 1 is
`accessible by dialing standard telephone numbers. These
`numbers are generally “off-premise” in relation to the orga-
`nization’s switching system 8, and 5. Central oflice switch-
`ing network 4 provides local loop service connecting an
`organization’s switching system 8 to the cellular switching
`network 1. Wireless PCS Networks 2 may also be accessible
`through central oflice switching network 4. Networks of
`antennae 3 exist for both cellular and wireless networks
`
`providing radio frequency communications with the cellular
`phones 14 and personal communications handsets 15. On-
`premise wireless handsets are supported through a wireless
`handset interface 7 which connects directly to the PBX
`Switching network 8. Wireless handset interface 7 commu-
`nicates via antennae 10 with handsets 11 on the customer
`
`premise. Standard analog telephones and digital feature
`phones 11 are connected directly to the on-prernise PBX
`switching network 8. For organizations with Centrex ser-
`vice, the analog telephones and digital feature phones 13 are
`connected directly to central oflice switching network 4
`within a Centrex partition 5.
`The PCS platform, which performs the functionality
`described in the inventions described herein, is located in
`either the central office 6, or on—premise 9. The PCS con—
`nects only to the switching system utilized in performing the
`service.
`Prior State of Art
`
`Calls which arrive at the PBX 8 or Centrex partition 5 are
`routed to the correct directly connected terminal. The cov-
`erage plan for the call is programmable, and the call may
`forward to additional telephone terminals 12, voicemail, or
`receptionist.
`The generally accepted practice is for organizations to
`prohibit off-premise forwarding and transferring due to
`potential toll-fraud abuses. Thus it would be invalid and not
`permitted to forward a PBX phone 12 to a Cellular phone 14.
`Another problem with off-premise forwarding and transfer-
`ring is that the control of the call is lost. Thus no further
`forwarding/transferring is allowed. Upon hangup of either
`side, the call is terminated.
`
`Typically, users of wireless services such as Cellular
`Telephone service have a separate telephone number for
`their “Cell Phone”. Callers must typically hangup a call to
`
`000007
`
`
`
`000007
`
`

`

`
`
`5
`
`6
`
`5,566,236
`
`an office number and dial the cellular telephone to gain
`access to the mobile person. Thus many mobile profession—
`als have multiple telephone numbers. The office number, the
`cell number, and their home number. Cell phones also
`supply out of service coverage, either in the form of an
`announcement, or a voicemail service. Many cellular users
`today must check their voicemail box at work, their voice-
`mail box at the cellular provider, and their home answering
`machine to stay in full communication. It is the objective of
`the invention to seamlessly integrate the cellular phones into
`an organization’s on-premise telecommunications system,
`including call coverage mechanisms such as personal opera—
`tors, receptionists, and voicemail.
`Wireless PCS networks have been announced, and will
`provide similar services as the cellular networks. These
`networks suffer from the same problems as the cellular
`telephones.
`The wireless telephones are also unreliable in comparison
`to wired telephones. Diseonnections are common without
`warning. It is another objective of the invention to detect
`unwanted disconnections, and to attempt
`to re-establish
`communications.
`
`Wireless telephones are relatively expensive to use com-
`pared to wired telephones. It is also an objective of the
`invention to move calls from wireless to wired and vice-
`versa, on command and at any time during a call.
`Cell Guard
`
`The PCS 6,9 is the mechanism through which the inven-
`tion is embodied. The PCS platform is described in U.S. Pat.
`No. 5,140,626, issued to Dry et al. on Aug. 18, 1992, with
`some additional hardware components. The block diagram
`of the PCS is shown in FIG. 2.
`
`Referring to FIG. 2, the block diagram shows the contents
`of the PCS system. All of the components are accepted as
`prior art, and are available commercially. The tandem matrix
`switch, voice processing components and/or an SS7 inter-
`face are the mechanisms through which the desired call
`control is obtained. Host switch 16 and host switch 17 show
`the external switching platforms. The SS7 processor 22 is a
`separate computer purchased on the open market which has
`a TCP/IP interface 21, and is connected to a signal transfer
`point 20 on the SS7 network.
`The invention connects into the organization’s switching
`system. The method of interconnection 18, and 19 can be
`through digital feature phone interface, ISDN basic rate, SS7
`common channel signalling and standard telephone inter-
`faces, feature group “D”, SMDI (SMSI) accompanied with
`standard lines, or any combination of the above. The method
`of interconnection is prior art. The interface must provide a
`means of determining the called party, and optionally the
`calling party. Furthermore, the embodiment of the invention
`depends on the types of call controls available with each
`interconnection method.
`
`Callers typically dial the business telephone number of
`their desired party. The organization may provide direct
`inward dial, permitting callers to directly ring their party’s
`desk telephone. Other organizations provide a receptionist,
`human or automated to route callers to their destinations.
`Either way,
`the desk top telephone will ring. After the
`desired number of rings, the call will forward using con—
`ventional means to PCS 9. Upon arrival, information about
`the called party and calling party will be obtained using
`common methods such as SMDI, ISDN, Feature Phone
`Emulation, SS7, etc (all prior art). If the called party,
`otherwise known as the subscriber has registered a cellular
`telephone with the PCS, the caller will be prompted to hold
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`40
`
`45
`
`50
`
`55
`
`65
`
`while the call is routed, and the cellular telephone will begin
`ringing. Once ringing,
`the cellular
`telephone can be
`answered directly by the subscriber.
`subscriber,
`the
`Another embodiment would permit
`through a voice processing means accessible through any
`touch tone phone, to become unavailable for cellular calls.
`This may be desired for periods of time during the day. This
`time of day control provides the highest level of screening.
`A further level of screening can be obtained by using an
`in-band or out—of—band data message sent over a wireless
`transmission network. This could include standard pagers
`utilized today, or CDMA cellular data transport methods
`being deployed. The message would arrive at the display
`terminal (pager, etc) providing information from the tele-
`phone network about who’s calling.
`A further level of screening can be obtained using voice
`processing means to prompt the caller for their number. This
`data can be sent of the wireless data link described above.
`
`A further level of screening can be obtained by using this
`data. The cellular user will be called. When the system
`answers, the user is prompted by an announcement of any
`required digits, followed by a menu of options, one of which
`is accepting the call.
`A further level of screening can be obtained using voice
`processing means to prompt the caller to speak their name.
`This is obvious to anyone skilled in the art. The distinction
`here is to use this name recording to identify calling parties
`to off—premise cellular users. The cellular user will be called.
`Upon answer, the name will be played followed by a menu
`of options, one of which is accepting the call.
`A further level of screening can be obtained by listening
`in to voicemail messages being left in real time. The system
`allows monitoring in synchronous or asynchronous modes,
`that is by listening to the message in real time as the speaker
`is leaving a message (synchronous) or by playing the
`message from the beginning, even though the speaker con-
`tinues to speak (asynchronous). The cellular user can listen
`to messages being left, and then decide to connect to the
`caller by pressing a DTMF key.
`When screening a call using these methods, the cellular
`user may act on the call through the menu. Using the menu,
`the cellular user may re-route the caller to another on-
`premise extension, re-route the caller to an ofi-premise
`telephone number, re-route the caller to voicemail, re—route
`the caller to a receptionist, or to hangup on the caller.
`Once a call has been accepted by the cellular user, the
`system will now monitor both sides of the call for hangup.
`This may be through directly carrying the talk-path utilized
`in the conversation, or through the use of “triggers” estab—
`lished for hangup events. Should the cellular user desire it,
`the CellGuard device may be used to watch over the cellular
`users or subscribers side of the call. Should the cell phone
`disconnect before the caller disconnects, the caller will be
`played a short menu. The menu will say “Your connection
`has been dropped. To re—establish your connection, press 1”.
`If the caller presses a key, or signals the desire to reconnect
`through any other voice processing means available to one
`skilled in the art (such as voice recognition), the PCS will
`call the cellular phone and attempt reconnection. Altema—
`tively, the system can be automated to automatically put the
`connected caller on hold, with a brief message such as
`“Signal lost. Please hold while we reestablish a connection-
`.”Whichever method is used, should reéonnection not be an
`option, the caller may leave a message in the on-premise
`voicemail system.
`Cellular users may not want callers to reconnect. To
`hangup on a caller,
`the cellular user can press either a
`
`.000008
`
`
`
`000008
`
`

`

`
`
`5,566,236
`
`7
`
`sequence of DTMF digits, such as pound, or hold down a
`DTMF digit, or through any other signaling mechanism
`available to one skilled in the art (flashes, etc). This will
`disconnect the caller, permitting the cellular user to continue
`performing other telecommunicating, including but not lim-
`ited to voicemail, calling another party, etc.
`During the time that a cellular user has a connection to a
`caller, should the cellular user desire to move the call to
`another wired or wireless terminal, the cellular user can
`simply pickup another terminal, dial into the PCS system,
`and through a voice processing means, identify themselves.
`The PCS system will
`interrupt
`the existing connection
`between the cellular phone, and the caller, to connect the
`caller to the new call. The cellular phone call will be
`disconnected.
`
`Another mechanism for switching terminals is to simply
`hangup the cellular phone. The caller will be prompted for
`reconnect as described above. Then the subscriber can call
`from any other terminal to connect with the caller.
`Another mechanism for switching terminals is to respond
`to a ringing cellular phone by pressing a code, such as a
`nearby extension number, to reroute the call to that extension
`before establishing a two-way communication.
`Another mechanism for switching terminals is to utilize a
`conference bridge to connect the caller, the cellular user, and
`the new call together, permitting uninterrupted communica-
`tion. At any time, the cellular telephone can be released from
`the conference.
`
`A cellular user can at any time call into the PCS and
`request that a conference be setup. The PCS can inform
`subscribers and callers that a conference setup is underway
`using conventional wireless data tools, such as pagers and
`cellular data terminals. The subscribers and callers can call
`into the PCS from off-premise wireless terminals, off-
`premise wired terminals, and on-premise terminals to par-
`ticipate in the conference.
`In all of the above descriptions of cellular integration, the
`function of the cellular phone can be replaced with any
`wireless phone,
`including a PCS wireless phone, or an
`on-premise wireless handset.
`Tandem Switching Embodiment
`One embodiment uses a tandem switch 23 to provide the
`features described above. Any tandem switch could be used,
`such as the Excel PCX512 manufactured by Excel, Inc. of
`Sagamore Beach Massachusetts. Tandem switch 23 carries
`the call either passively (without the callers knowing) or
`actively (with voice prompts and instructions). Tandem
`switch 23 can convert from one signaling protocol
`to
`another. For example, tandem switch 23 can connect pri-
`mary rate lines to analog lines. This capability for protocol
`conversion is required to connect calls from a variety of
`sources.
`"
`
`A call will arrive on a desktop phone 12 or 13 after being
`directed their by the host switch, either a PBX'8 or central
`oflice switch 4 as part of a Centrex partition 5. The call will
`ring the physical terminals programmed for the particular
`directory number dialed. Upon a ring-no-answer or busy
`condition, the call will be forwarded to the PCS 9, or 6 with
`information about who was called, and optionally, who is
`calling. The information may be transmitted with the call or
`out-of-band using standard mechanism available to those
`skilled in the art, including but not limited to SMDI (SMSI),
`ISDN Primary Rate, ISDN Basic Rate, Proprietary Feature
`Phone Interface, Inband DTMF, Feature Group
`SS7
`Common Channel Signaling, etc. The call will arrive on the
`tandem switch 23 via one of the supported protocol interface
`components.
`
`10
`
`15
`
`20
`
`25
`
`30
`
`35
`
`45
`
`50
`
`55
`
`60
`
`65
`
`8
`The PCS will use this information to either immediately
`begin the sequence of steps to connect the caller to the
`wireless device, or to prompt the caller for information used
`for screening purposes. If the screening process requires
`voice processing elements 24, they are connected to the
`arriving call by the tandem switch 23. Standard voice
`processing elements are used, such as the Dialogic (TM)
`D121 Digital Signal Processor boards manufactured by
`Dialogic, Inc. Parsippany, NJ. Additional voice processing
`boards may be used for reception of facsimile, modern data
`calls. For example, the Dialogic (TM) Fax120 Fax Processor
`boards manufactured by Dialogic, Inc. Parsippany, NJ.
`The voice processing elements can be used to play menus,
`perform voice recognition, gather DTMF digits, etc.
`to
`obtain the screening information desired.
`The arriving call will be placed on hold, or parked by
`tandem switch 23. The caller may hear ringback, music on
`hold, prompts, or silence, depending on the desired appli-
`cation set. To connect the caller to a wireless device, PCS 6,9
`will instruct tandem switch 23 to outseize a new commu-
`
`nication path to the host switch 4,8 respectively. If the PCS
`is connected to a PBX 8, then the outseize will be propagated
`to the central office. This outseize can be of many forms, and
`is dependant on the signaling protocol used for connections
`18, 19. The outseize will be propagated to wireless trans-
`mission source 1, 2, 7 through the central office switch 4, or
`PBX 8 as required. The outseize will be complete when the
`digits desired have been dialed or digitally communicated to
`the host switch, and an ringing (or answer) is returned.
`At this point, a communication path exists between the
`wireless transmission source 1, 2, 7 and the PCS 6, 9 through
`tandem switch 23. The communication path provides com-
`plete voice and electrical signaling to support a telephone
`call.
`
`The wireless transmission source 1, 2, 7 will then begin
`alerting the wireless handsets 11, 14, 15 which if in the
`reception area, will emit a ringing tone. If the wireless
`handset is answered, answer supervision will be returned
`from the handset to wireless transmission source 1, 2, 7.
`Once the answer has been returned to wireless transmission
`source 1, 2, 7, the communication path is allocated, and the
`talk path between the handset 11, 14, 15 and wireless
`transmission source 1, 2, 7 is complete.
`The wireless transmission source returns the answer
`supervision to central office switch 4 or PBX 8 which
`propagates the signal to PCS 6, or to PBX switching network
`8, whichever is appropriate. If the later case,
`the PBX
`forwards this answer supervision to PCS 9.
`The PCS will optionally wait for an answer, and then
`optionally instruct tandem switch 23 to connect voice pro-
`cessing elements 24 to the call
`to play a menu to the
`subscriber providing screening information as described
`above. The subscriber may choose to answer the call, place
`the call in voicemail, re-route the call to another number, etc.
`This choice is entered using voice processing means like
`DTMF key presses, or voice recognition. The choice is
`effected by tandem switch 23, and cooperating voice pro-
`cessing elements 14. If the call
`is accepted, the tandem
`switch will disconnect all voice processing resources 24, and
`connect the caller to the subscriber. FIG. 3 shows this
`connected scenario utilizing a PBX.
`Referring to FIG. 3, an arriving call 26 is extended
`through central oflice switch 28 to on-premise PBX or
`Centrex partition 25. The call may be directly routed to a
`desktop phone 33, or routed directly to the PCS 30 for
`processing. If routed to a desktop phone 33, the PCS will be
`
`000009
`
`
`
`000009
`
`

`

`
`
`9
`
`10
`
`5,566,236
`
`placed into the coverage plan for that phone. Upon ring—no-
`answer or busy, the call will forward to PCS 30, and will be
`answered by tandem switch 29. When the call arrives,
`information about who is calling, and who was called is
`obtained through various mechanisms not shown, but obvi-
`ous to those skilled in the art. Tandem switch 29 will hold
`the call throughout the length of the call, permitting con-
`nection a