US006324404B1
`
`a2 United States Patent
`
`Dennison et al.
`
`(10) Patent No.:
`5) Date of Patent:
`
`US 6,324,404 B1
`#Nov. 27, 2001
`
`(54)
`
`(75)
`
`(73)
`
`*)
`
`@D
`(22)
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`(63)
`
`CELLULAR TELEPHONE SYSTEM THAT
`USES POSITION OF A MOBILE UNIT TO
`MAKE CALL MANAGEMENT DECISIONS
`
`Inventors: Everett Dennison, Canficld, OH (US);,
`Timothy J. Duffy, West Middlesex, PA
`(US); Gregory T Pauley, Canficld, OH
`(US); Scott L. Jones, Sharon, PA (US);
`Albert H. Pharis, Jr., Canfield;
`Warren P. Williamson, IV, Loveland,
`both of OH (US)
`
`Assignee: Sycord Limited Partnership, Zephyr
`
`Cove, NV (US)
`
`Notice: This patent issued on a continued pros-
`ecution application filed under 37 CFR
`1.53(d), and is subject to the twenty year
`patent term provisions of 35 U.S.C.
`
`154(a)(2).
`
`Subject to any disclaimer, the term of this
`patent is extended or adjusted under 35
`U.S.C. 154(b) by 0 days.
`
`This patent is subject to a terminal dis-
`claimer.
`
`Appl. No.:
`Filed:
`
`08/848,082
`Mar. 21, 1996
`
`Related U.S. Application Data
`
`Continuation-in-part of application No. 08/813,494, filed on
`Mar. 7, 1997, now Pat. No. 6,006,106, which is a continu-
`ation-in-part of application No. 08/555,884, filed on Oct. 23,
`1995, which is a continuation-in-part of application No.
`08/402,976, filed on Mar. 13, 1995, which is a continuation
`of application No. 08/057,833, filed on May 7, 1993, which
`is a continuation of application No. 07/813,494, filed on
`Dec. 26, 1991, now Pat. No. 5,235,633.
`
`(FROM 107 FIG. 8)
`
`(51) Int.Cl7 H04Q 7/20
`(52) US.ClL . 455/456; 455/406; 455/432
`(58) Field of Search 455/422, 432,
`
`455/436, 440, 456, 405-409, 445
`
`References Cited
`
`(56)
`U.S. PATENT DOCUMENTS
`
`5,235,633 * 8/1993 Dennison et al. .....ccecerveennene 455/456
`5,303,297 * 4/1994 Hillis .cccoeevevreneencnecereeeenne 455/406
`5,546,445 * 8/1996 Dennison et al. .....ccccoeeeueene 455/456
`
`FOREIGN PATENT DOCUMENTS
`
`2-210923 * 2/1989 (IP).
`
`* cited by examiner
`
`Primary Examiner—Dwayne D. Bost
`Assistant Examiner—Nay Maung
`(74) Attorney, Agent, or Firm—Terry M Gernstein
`
`(7) ABSTRACT
`
`A cellular telephone system has call management decisions
`made based on the exact geographic location of the mobile
`unit. These call management decisions include billing and
`taxing decisions, cell site selection, frequency selection and
`even cellular system selection. The decisions are continu-
`ously updated during a call whereby decisions can be made
`and changed regardless of where a call originated. Cell site
`location, and even cellular system selection, can be made in
`a specific manner to best serve the needs of the mobile user,
`the cellular system as well as the public. It is even possible
`for a cellular system to locate one or more of its cell sites in
`the geographic area served by another cellular system. In
`some cases, cellular systems might even share cell sites.
`
`41 Claims, 21 Drawing Sheets
`
`'CD IDENTIFIED FOR
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`{70 108 FIG. 8)
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`FIG. 9B
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`(107 OF FIG. 8)
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`U.S. Patent
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`Nov. 27, 2001
`
`Sheet 1 of 21
`
`US 6,324,404 Bl
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`BASE
`~ /©
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`MOBILE
`- =
`FROM/TO 18 14 15 FROM/TO 8 4
`BASE MOBILE
`ANTENNA ANTENNA 6
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`RECEIVER : TRANSMITTER RECEIVER ! TRANSMITTER "O
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`U.S. Patent Nov. 27, 2001 Sheet 2 of 21 US 6,324,404 B1
`
`IDLE MOBILE UNIT SCANS
`OVERHEAD MESSAGE TO
`DETERMINE WHAT CELL
`SIGNAL IS STRONGEST.
`
`y
`
`MOBILE UNIT LOCKS
`ONTO THAT CELL.
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`LAND INITIATED CALL
`TRANSFERRED FROM
`TELEPHONE TO MTSO.
`ANEIGHBOR CELL WILL IDENTIFY
`‘ THAT IT HAS THE MOBILE UNIT
`AT A PARTICULAR STRENGTH
`MTSO SENDS OUT A ‘
`“LOCATE REQUEST” ‘
`SIGNAL TO ALL CELLS, TS0 COMPARES NEW
`‘ STRENGTH WITH TABLE OF
`: ALLOWABLE SIGNAL STRENGTHS.
`THAT CELL RELAYS ID
`INFORMATION TO MTSO : ‘
`STS;ITNSEWSBT&ESSS.CE MTSO SIGNALS MOBILE
`UNIT VIA OLD CELLTO
`‘ RETUNE TO NEW CELL.
`MTSO ESTABLISHES VOICE *
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`MOBILE UNIT VIA THE CELL. MOBILE UNIT RETUNES
`‘ TO NEW CELL.
`CELL CHECKS SIGNAL STRENGTH. L
`MTSO RE-ROUTES
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`UNIT TO THE NEW CELL.
`IF SIGNAL STRENGTH DROPS
`BELOW A THRESHOLD LEVEL,
`CELL SIGNALS MTSO.
`MTSO SENDS OUT A F l G : 2 :
`“LOCATE REQUEST” PRIOR ART
`TO ALL NEIGHBOR CELLS,
`
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`US 6,324,404 B1
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`Sheet 3 of 21
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`Nov. 27, 2001
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`U.S. Patent
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`U.S. Patent Nov. 27, 2001 Sheet 4 of 21 US 6,324,404 B1
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`US 6,324,404 B1
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`Nov. 27, 2001
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`U.S. Patent Nov. 27, 2001 Sheet 8 of 21 US 6,324,404 B1
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`BASE 22
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`US 6,324,404 B1
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`Sheet 9 of 21
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`Nov. 27, 2001
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`U.S. Patent
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`U.S. Patent
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`Nov. 27, 2001
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`Sheet 10 of 21
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`| CD POWERUP flfl
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`ONLINE USES
`(REAL TIME)
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`—
`
`— EGL RECORDED
`FOR BILLING
`
`EMERGENCY
`> 911
`120
`B TAXES
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`121
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`e CP RATING
`(FIG 9A) 122
`
`CUSTOMER
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`123
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`| FREQUENCY ,,
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`|(F.G o) REGISTRATION PROCESS 102 |
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`[¢Fio9) REGISTRATION PROCESS 1 |
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`US 6,324,404 B1
`
`CHANGING FREQ.
`—®] DUAL FREQUENCY
`(FIG 14) 125
`
`— CHANGE
`CELL SITE 1%
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`| CHANGE CELL
`SYSTEM
`
`(FiGeB) CP ROUTING 107 | ONE-TIME
`OFFLINE USES
`COMMUNICATIONS
`ESTABLISHED 108 E(EIE)SEB(I:E)LTS(I;ED
`+ > 109
`STORE EGL FOR CP
`MANAGEMENT & BILLING 114
`EMERGENCY
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`114A 1148 110
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`UPDATE EGL 15 ] CP RATING
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`USE UPDATED EGL FOR CP CUSTOMER
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`[ CP COMPLETED 18 I
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`FIG.8.
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`U.S. Patent Nov. 27, 2001 Sheet 11 of 21 US 6,324,404 B1
`r— = —— = — — = —
`(FROM 101, 105 OF FIG 8)
`GPS 202
`
`CD EGL DETERMINED
`
`201
`
`SIGNAL STRENGTH 203
`
`LORAN 204
`
`HOME SYSTEM
`
`HOME SYSTEM LOCATION
`SERVICE BOUNDARIES
`
`205
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`SERVICE BOUNDARY
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`HOME
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`CELL LIST
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`FREQUENCY 206
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`SYSTEM?
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`REDIRECT NEIGHBOR
`o 211 N1 ?
`I NEIGHBOR N2
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`REDIRECT NEIGHBOR EGL DETERMINED
`I Cch 215 Nz ? ‘ 216
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`| FIG. 9 NNTH *
`REGISTRATION PROCESS
`|_ (102, 106 FIG. 8) (TO 103, 107 OF FIG. 8)
`
`
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`U.S. Patent
`
`Nov. 27, 2001
`
`Sheet 12 of 21
`
`(FROM 109. 119 FIG. 8)
`
`!
`
`SUBSCRIBER
`DATABASE
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`DC IDENTIFIED
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`US 6,324,404 Bl
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`EGL COMPARED TO
`CP RATING TABLE
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`CP RATING
`TABLE
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`RATING CHOSEN
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`RECORD EGL AND TIME
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`FOR CP RATING
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`(TO 109, 119 FIG. 8)
`
`FIG. 9A
`CP RATING
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`
`U.S. Patent
`
`Nov. 27, 2001
`
`Sheet 13 of 21
`
`US 6,324,404 Bl
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`I_—'_'__———___——_——___—]
`| (FROM 107 FIG. 8) l
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`US 6,324,404 Bl
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`Sheet 14 of 21
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`Nov. 27, 2001
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`U.S. Patent
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`U.S. Patent Nov. 27, 2001 Sheet 15 of 21 US 6,324,404 B1
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`CELLULAR TELEPHONE SYSTEM THAT
`USES POSITION OF A MOBILE UNIT TO
`MAKE CALL MANAGEMENT DECISIONS
`
`TECHNICAL FIELD OF THE INVENTION
`
`The present invention relates to the general art of wireless
`over-the-air communication, which includes cellular mobile
`radiotelephone (CMR) technology, and to the particular field
`of managing communication processes in a wireless over-
`the-air communication system. The present application is a
`continuation-in-part of pending U.S. Application Ser. No.
`08/555,884, filed Oct. 23, 1995 which is a continuation-in-
`part of U.S. application Ser. No. 08/402,976, filed Mar. 13,
`1995, which was a CIP of U.S. application Ser. No. 08/813,
`494, filed Mar. 7, 1997 now U.S. Pat. No. 6,006,106, issued
`on Dec. 21, 1999, now U.S. Pat. No. 5,235,494 which is a
`continuation of U.S. application Ser. No. 08/057,833, filed
`May 7, 1993 which is a continuation of U.S. application Ser.
`No. 07/813,494, filed Dec. 26, 1991 and issued as U.S. Pat.
`No. 5,235,633. The disclosures of each of these applications
`is fully incorporated herein by reference. Therefore, as used
`hereinafter, the term “prior art” refers to art that is relevant
`prior to the invention dates associated with this incorporated
`material.
`
`BACKGROUND OF THE INVENTION
`
`The present invention is concerned with wireless over-
`the-air communication using a plurality of transmit/receive
`cell sites or relay points. It should be understood that the
`transmit/receive relay points can be either land based or
`non-land based, such as satellite based, and that as used
`herein, the term “cell site” or its equivalent refers to one of
`the relay points of the system. CMR (Cellular Mobile Radio)
`is an example of one type of wireless over-the-air commu-
`nication system that can be included in the present disclo-
`sure. It is understood that the term CMR is not intended to
`be limiting, but is merely used as an example for the
`purposes of discussion. It is also to be understood that the
`term “cellular telephone system” or its equivalents is
`intended to be shorthand notation for the term “wireless
`over-the-air communications system” and no limitation is
`intended by the use of the term “cellular.” Also, as used
`herein, the terms “CD (Communication Device)” and “MU
`(Mobile Unit)” are intended to include any device used to
`communicate in the wireless over-the-air communication
`system. Also, the term “cellular telephone system” is used
`for purposes of discussion but can include any form of
`wireless over-the-air communication system. It is also noted
`that many forms of communication are and will be con-
`ducted over the wireless over-the-air networks. Therefore,
`the present disclosure will refer to a “communication pro-
`cess” which is intended to cover calls as well as other forms
`of communication that can be conducted in this manner.
`
`CMR is a rapidly growing telecommunications system.
`The typical CMR system includes a multiplicity of cells. A
`particular geographic area can be subdivided into a multi-
`plicity of subareas, with each of the subareas being serviced
`by a stationary transmitter/receiver setup. The cells are set
`up to carry signals to and from mobile units in the range of
`the cell. If one cell site becomes too crowded, it can be
`divided into smaller cells, by a process known as cell site
`splitting. Any particular geographic area can become quite
`complicated with cells overlapping each other, and overlap-
`ping cells of other neighboring cellular systems. Further,
`null zones with inadequate coverage, or even no coverage,
`can result. It is noted that the term “cellular” is intended to
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`be a term of convenience, and is not intended to be limiting.
`The present disclosure is intended to encompass any com-
`munication system in which an overall area can be divided
`into one or more subareas, and also to any communication
`system having at least some portion of the communications
`occurring over the air.
`
`A typical CMR set up is indicated in FIGS. 1 and 2, and
`will be described so an understanding of the problem to
`which this invention is directed can be obtained.
`
`Shown is a typical cellular telephone unit having a unique
`mobile identification number stored in a suitable location
`such as an electrically erasable programmable read-only
`memory (not shown). Telephone units of this kind are
`known to those skilled in this art, and thus will not be
`described in detail.
`
`The telephone unit includes a handset 4 having a keypad
`5 as well as a speaker 6 and a microphone 7. A transceiver
`8, ordinarily built into the telephone unit, exchanges signals
`via an antenna 10 with a mobile telecommunications switch-
`ing office or MTSO 12 via a cell site 14. A duplexer 15
`connects the antenna to the transceiver. The cell site 14
`includes an antenna 16 connected to a control terminal 17
`via a transceiver 18. The cell site 14 is connected to the
`MTSO via a transmission link 20. The Mobile Telephone
`Switching Office has historically been known as the center
`of the wireless over-the-air communications system. It is
`where the communication process management decisions
`are made, billing records are produced and where mainte-
`nance activities are initiated for wireless over-the-air com-
`munications systems. The MTSO is not a specific piece of
`equipment, but is comprised of many individual pieces. The
`MTSO will contain a telephone switch, peripheral
`processors, adjunct processors, and various other informa-
`tion gathering equipment used in the operation and man-
`agement of a wireless over-the-air communications system.
`Each of the different pieces of equipment may directly or
`indirectly be involved providing the highest quality connec-
`tion possible. The makeup of the MTSO therefore comprises
`many different pieces of equipment and many components,
`which can be supplied by different vendors. Therefore,
`communication process management decisions made at the
`MTSO can actually be made outside of a switch and can be
`made in a cluster of nodes housed along the network or even
`in separate cell sites. Therefore, as used herein the term
`MTSO really refers to all of the systems, nodes, modules,
`equipment and components that combine to define a wireless
`over-the-air communication process management network,
`regardless of the physical or system location of these ele-
`ments. The term MTSO therefore is not intended to be
`limiting to the “switching off ice” as it may have been
`viewed in the prior art. The term is intended to be much
`broader than that and to include any combinations of
`equipment, etc that may be connected within the commu-
`nication processing network of the service provider. The
`term MTSO is one of convenience and is intended to include
`all the information processing hardware and software asso-
`ciated with the wireless over-the-air communication process
`management process within a wireless over-the-air system,
`no matter where the hardware or software is located in the
`system. It is also noted that the term “intrasystem” refers to
`actions and components within a particular system; whereas,
`the term “intersystem” refers to actions and components
`located outside a particular system.
`
`Referring to FIGS. 1 and 2, the operation of the CMR can
`be understood. The mobile unit M moves about the geo-
`graphic areas covered by the various cells. As that mobile
`unit moves about, it decodes the overhead message control
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`signals generated by various cell site control channels. The
`mobile unit locks onto the cell site that is emitting the
`strongest signal. The mobile unit rescans channels periodi-
`cally to update its status. If, for example, a fixed-position
`land-based telephone T is used to call the mobile unit, a
`signal is sent via landlines L, to the central office CO of a
`public/switched telephone system (PTSN) 12A. This system
`then utilizes the switching network SN associated therewith
`to call the MTSO 12 via a transmission link L1. The MTSO
`then utilizes its own switching network and generates a page
`request signal to cell sites via transmission links, such as the
`transmission link 20. The cell site which has been notified of
`the presence of the mobile unit M sends a signal back to the
`MTSO via the landlines or wireless links alerting the MTSO
`of the presence of the mobile unit. The MTSO then orders
`the mobile unit, via the notifying cell site, to tune to an
`assigned channel and receive the communication process.
`
`On the other hand, during communication process
`origination, the mobile unit rescans the control channels to
`determine which is the best server based on signal strength.
`Upon selecting the best server, the mobile unit transmits cell
`site information on the control channel receive frequency
`and then receives a voice channel to tune to if the mobile unit
`is authorized to place a communication process.
`
`As the mobile unit moves, the signal strength between that
`mobile unit and the originating cell site changes, and per-
`haps diminishes. Since signal strength is an inverse function
`of the square of the distance between the mobile unit and the
`cell site, signal strength can change rapidly and drastically
`as the mobile unit moves with respect to the cell site and
`therefore must be monitored closely. The MTSO has a signal
`strength table, and signal strength from the mobile unit is
`constantly compared to acceptable signal strength levels in
`the table. Such a table can be located in each cell site if
`desired.
`
`Should signal strength diminish below a preset range, the
`MTSO generates a “locate request” signal to all cell sites
`that neighbor the original cell site. Each of such neighboring
`cell sites receiving a signal from the mobile unit signals the
`MTSO, and the signal strengths from such neighboring cell
`sites are checked against the signal strength table. The
`MTSO makes a decision as to which cell site should control
`the communication process, and notifies the original cell site
`to order the mobile unit to retune to a voice channel of the
`new cell site.
`
`As soon as the mobile unit retunes, the mobile unit
`completes the communication process via the new cell site
`channel. This transfer of control is known as a handoff.
`
`Typically, governments grant rights to provide wireless
`communication services to a specified land area based on
`geographic boundaries. Since wireless propagation does not
`end at exact geographic boundaries, many conflicts have
`arisen between service providers as to which service pro-
`vider should provide service at the location from where the
`Communication Process (CP) is being originated or
`received. Today, there are no methods or procedures to
`resolve these issues. A Communication Process (CP) can be
`defined as the exchange of information between communi-
`cation devices, such as, but not limited to, Analog or Digital
`radiotelephones, digital data communications, analog or
`digital video, and the like.
`
`When the initial wireless systems were built, they were
`constructed around major metropolitan areas. This created
`service voids between major metropolitan markets. In these
`early systems, boundary service problems did not arise
`because there were areas of “no service” buffering compet-
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`ing systems. Today, as rural systems fill in the patchwork of
`nationwide coverage, network service provision boundary
`disputes are becoming common. Prior to the Dennison, et al
`patent, U.S. Pat. No. 5,235,633 and the patents and appli-
`cations depending therefrom as continuations and
`continuations-in-part, the disclosures of which are fully
`incorporated hereinto by reference, and the invention dis-
`closed herein, it was impossible to honor the exact geo-
`graphic boundaries. Attempts are currently made to control
`coverage boundaries by installing directional antennas and
`adjusting cell site receive and transmit parameters. The
`methods used to match the system boundaries to the geo-
`graphic boundaries are not entirely successful due to the
`variations in terrain, environment and limitations of antenna
`design and wireless propagation. A common result of these
`problems is inadequate wireless signal strength or null
`coverage and border disputes around the geographic bound-
`aries and hence poor service.
`
`The incorporated material, including the Dennison et al
`patent disclose that cell sites sometimes have overlapping
`coverage due to the aforementioned variations in terrain and
`environment, and propose a solution. While the proposed
`solution works well, there is still room for further improve-
`ment in the areas of cost, subscriber service, billing and
`taxing.
`
`Furthermore, wireless propagation, such as but not limited
`to the cellular operating band of 800-900 MHz, is generally
`line-of-site transmission. This presents substantial chal-
`lenges when choosing sites in which to place wireless
`transmit/receive antennas. Boundaries assigned to service
`providers are based on maps depicting the geographic bor-
`ders of service boundaries. The question arises in a disputed
`territory of who will get to service the Communications
`Process (CP). In the past, it has been the cell site that can
`provide the highest signal strength from the CD
`(Communications Device), not the provider that owns the
`legal territorial rights to the Communication Process (CP)
`that has serviced the Communication Process (CP). Until the
`invention disclosed herein, the service provider that could
`receive the best signal would handle the communication
`process (CP), and depending on whether the Communica-
`tion Process (CP) was handed off and/or depending on the
`agreement made between the wireless communication
`systems, possibly keep all of the revenue from the commu-
`nication process CP. Additionally, with real estate values
`being very high in established communities, cell sites are
`harder to construct and more expensive to build. Each cell
`site must be optimized for the maximum effective coverage
`area to overcome the real estate problems encountered when
`constructing a cell site. This in turn creates problems with
`overlapping coverage between wireless systems and thus
`disputes over which wireless system handles the communi-
`cation process. Further, due to business considerations, it
`may be economically advantageous for one wireless system
`to own a cell site which is geographically located in the
`geographic area of another wireless system.
`
`Cell sites are very expensive to install and maintain, so
`there is a very real savings for a service provider if fewer cell
`sites could be constructed while also improving coverage.
`Another area that would be affected by this is problems of
`quality service. This is because the service provider has
`conflicting requirements. To provide good coverage next to
`borders the provider would like to have high signal strength.
`To allow for hand-offs between cell sites and networks the
`signal strength needs to “fade out” at just the right level near
`the border to invoke a low threshold to start a hand-off
`process. It would be ideal to have high signal strength right
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`up to a geographic boundary and then drop off beyond that
`boundary. However, at the present time, presently available
`systems do not permit this type of coverage.
`
`Some areas inherently have wireless propagation
`problems, such as service areas next to bodies of water or in
`steep valleys. Wireless propagation can provide some very
`undesirable results for a number of reasons, some of which
`have been mentioned above and in the incorporated mate-
`rial. Therefore, there is a need to provide each network
`information as to which system has a right to handle a
`Communications Process (CP). For instance, a communica-
`tions device (CD) might attempt to select a geographically
`incorrect service provider. Therefore, there is a need for a
`system that will permit a service provider to redirect the
`communication process to the geographically correct service
`provider, especially in a manner that is transparent to the
`Communications Device (CD) user.
`
`Since cellular system geographic borders can be non-
`linear and can have irregular shapes, problems can arise.
`Problems associated with irregular boundaries are indicated
`in FIG. 3. FIG. 3 graphically shows the problem of obtaining
`coverage for areas that have irregular boundaries. In this
`figure, areas A and C are serviced by Carrier X, and area B
`is serviced by Carrier Y. It is noted that areas A and C are
`intrasystem with respect to Carrier X and area B is intra-
`system with respect to Carrier Y, while areas A and C are
`intersystem with respect to Carrier Y and area B is inter-
`system with respect to Carrier X. It is also noted that areas
`A and B could be covered by just one cell site each but the
`overlap into adjacent territories would be difficult to resolve.
`Today, areas such as these would be split into two or more
`cell sites. For instance, Carrier X might elect to install three
`cell sites Al, A3 and A4 which provides a minimum of
`overlap into area B. Overlap is indicated at the shaded areas.
`Therefore, there is a need for a system what would allow
`Carrier X to install a cell site with a larger coverage area
`such as A2 (shown in dotted lines).
`
`FIG. 4 shows a prior art attempt of providing sectored
`cells. Using prior art technology requires installation of
`directional antennas to minimize the overlap into neighbor-
`ing territory in order to resolve a border issue. Since these
`antenna patterns cannot be made to follow curved geo-
`graphic borders, sectors are installed and directed for the
`best geographic coverage possible. This often involves
`obtaining a cell site location close to the border and “shoot-
`ing back” toward the wireless communication system’s own
`territory. This can leave null zones where cells back onto
`each other in an effort to keep signals from overlapping into
`neighboring territory. These null zones will have either poor
`quality service or even no service at all, thereby resulting in
`poor service. Therefore, there is a need to overcome this
`problem as well.
`
`FIGS. 5A and 5B illustrate a problem of how geographic
`terrain can affect prior art systems. In FIGS. 5A and 5B, a
`small rural network A is located just across the river from a
`large city C, which is part of a neighboring network B. The
`river defines the geographic and legal border between these
`two systems. The city C is in another state just across the
`river. In some river towns, there is a bluff on each side of the
`river. The network A can place their cell sites very near the
`border atop the bluff providing overlapping coverage into
`the city C. Network A will get all the service of the
`neighboring community D further away from the city C.
`Network A now has better line of cell site reception into the
`river valley with its corresponding traffic at river level than
`does network B who legally “owns” the territory. Network
`B would have to install additional cell sites in the river
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`valley to obtain the same coverage. Due to the stronger
`signal level provided by Network A, Network A will process
`a communications process (CP). The result is that subscrib-
`er’s Communication Process (CP) may not be processed by
`the correct service provider.
`
`Note in FIG. 5A that there are two service providers X and
`Y. The intersystem boundary is shown as a dashed line down
`the middle of the river. With a bluff on either side of the
`river, the cells can only service the opposite bluff. This is
`shown where Y1 cell site cannot “see” the subscriber CD'
`hidden below. cell site Y1 can however find CD3 in service
`provider X’s territory. This issue denies revenue to the
`wireless communication system that has legal right to serve
`the subscribers within its licensed geographic service bound-
`aries. Prior art systems are incapable of determining the
`geographic location of both the communications devices and
`their service boundaries and thus compromise quality of
`coverage. Therefore, there is a need to resolve this issue.
`
`There is also need for providing a wireless over-the-air
`communication system with the ability to adjust its coverage
`and billing as the mobile unit moves. This will permit the
`system to determine taxes based on where the communica-
`tion process is actually being made as opposed to the criteria
`used with the prior art. Still further, there is a need to permit
`a wireless over-the-air communication system to change
`frequencies as the mobile unit moves whereby a single
`wireless service provider can provide service to its subscrib-
`ers regardless of frequency.
`
`Still further, due to various business reasons, a single cell
`site may advantageously be u