Note: Descriptions are shown in the official language in which they were submitted.
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System and Method for Selecting A Desired Service Provider
Background of fhe Invention
1. Field of the Invention
This invention relates generally to wireless communication systems and
more specifically to a system and method for selecting a desired service provider
in a wireless communication system.
2. R~ t~d Art
The first generation of cellular technology, advanced mobile phone
system (AMPS) has enjoyed much success in the telecommunications industry.
In fact, AMPS has become so successful that demands for its service are far
exceeding the available capacity in certain metropolitan areas.
New technologies for personal communications are emerging to take
advantage of the high dem~n-l for mobile communications and to attempt to offer
1~ enhanced services and/or performance. One such new technology is the Personal
Communications Services (PCS). Several systems have been implemented to
provide PCS functionality. One common service is the CT-2 (cordless telephone
2) service which is being adopted as a standard in many countries.
Whether the technology is AMPS or PCS, the equipment and service
provider market is primarily domin~ted by a handful of vendors. However, as
d~m~nris increase new players continue to enter the market to offer products and
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services. To allow multiple carriers to share the available communications
bandwidth, the spectrum is divided and allocated among the various carriers. Forexample, in current AMPS implementations the frequency spectrum is divided
into two frequency bands. These are referred to as the A-side and B-side of the
5 frequency spectrum. For PCS, it is envisioned that the spectrum be divided into
6 different frequency bands referred to as A, B, C, D, E, and F bands.
One recent phenomenon beginning to emerge among vendors is the
reseller service provider. A service reseller planning to enter the
communications market purchases communications services from a primary
10 provider and re-sells the service to its own customers, or subscribers.
Typically, as a mobile subscriber travels (or "roarns") from one cell to the
next, his or her service is handed off to the carrier in the new cell. Traditionally,
the carrier used by the subscriber occupies the same portion of the frequency
spectrum from cell to cell. Therefore, as the subscriber roams to a new cell, there
15 is no need to change the operating frequency of the subscriber's mobile
telephone.
However, where the service provider is a reseller company, the service
provider may have arrangements with different carriers in different geographic
areas. Therefore, as the subscriber of the reseller provider moves from one region
20 to the next, the primary carrier may change and so may the portion of the
frequency spectrum allocated to handle the subscriber's call.
When this occurs, the subscriber has to m~nll~lly switch the frequency to
the correct band that is used by the carrier in the new region. This may be
accomplished by the subscriber m~nn~lly reprogr~mming his or her telephone
25 (also referred to as mobile terminal, or mobile telephone terminal).
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Summary of ~he Invention
The present invention is directed toward a system and method for
det~rmining whether a subscriber's desired service provider is operating on a side
of the spectrum in a subscriber's current geographic area when that subscriber is
5 roaming out of his or her home geographic area.
When roarning outside of his or her home geographic area, the subscriber
initiates a service request to a service provider in his or her current geographic
area. This request can be made by powering up the mobile telephone or initiatinga telephone call. This request is, by default, made to the service provider in the
10 current geographic area servicing the side of the spectrum on which the
subscriber typically operates. This service provider is referred to as the default
service provider.
First, a check is made to determine whether this default service provider
is a desired service provider. That is, it is (1et~nnined whether the default service
15 provider is either the same as the desired service provider or whether the default
service provider has a service agreement with the reseller through which the
subscriber obtains service.
If the default service provider is a desired service provider, the service
request is granted and the subscriber is free to place and receive calls. If, on the
20 other hand, the default service provider is not a desired service provider, it is
determined whether a desired service provider is available on another band of the
spectrum in the current geographic area.
If a desired service provider is not available on another band of the
spectrum in the current geographic area, the subscriber is provided the option of
25 continning service with the default service provider.
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If, however, a desired service provider is available on another band of the
spectrum in the current geographic area the subscriber (and/or his or her mobiletelephone) is so notified. A message or other such indication is provided
indicating that the a desired service provider is available on another band of the
S spectrum in the current geographic area. The message can inform the subscriberto switch bands, or the message can inform the subscriber's telephone to switch
bands so that the subscriber need not take any special steps to obtain service.
An advantage of the invention is that the subscriber can obtain service
from a desired service provider in a foreign (i.e., away from home) geographic
10 area without having to take any special action. The subscriber need not
reprogram his or her mobile phone. Further, the subscriber does not even need
to know that the change has been made and the subscriber does not need to keep
track of service providers in various roaming areas.
Another advantage is that when the subscriber roams from one geographic
15 area to the next while engaged in a communication, the change can be made
without a disruption of service to the communication.
Further features and advantages of the present invention, as well as the
structure and operation of various embodiments of the present invention, are
described in detail below with reference to the accompanying drawings.
Brief Description of the Drawings
The present invention is described with reference to the accompanying
drawings. In the drawings, like reference numbers indicate identical or
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functionally similar elements. Additionally, the left-most digit of a reference
number identifies the drawing in which the reference number first appears.
FIG. 1 is a diagram illustrating an example environment of the invention.
FIG. 2 is an operational flow diagram illustrating a process by which a
desired service provider is selected according to one embodiment of the
invention.
FIG. 3 is an operational flow diagram illustrating a process by which a
home location register determines whether a desired service provider is available
according to one embodiment of the invention.
FIG. 4 is an operational flow diagram illustrating a process by which the
mobile telephone automatically accesses the desired service provider according
to one embodiment of the invention.
De~i~e~ Description of the Embodiments
1. Overview and Discussion oSt/te Invention
The present invention is directed toward a system and method for
selecting a subscriber's desired service provider in a wireless communication
system, such as a cellular communication system. More specifically, the system
and method provides the subscriber with service by his or her desired service
provider regardless of the side of the spectrum on which that provider is operating
20 in the subscriber's current geographic area
According to the invention, a system and method determines whether the
subscriber is requesting service from a desired wireless service provider in thesubscriber's current geographic area. If so, the service request is registered. If
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not, the system and method determines whether the service is available from the
desired service provider on a dirr~lell- side ofthe ~e~ l. The manner in which
this is accomplished is described in detail below.
2. Example Environment
Before describing the invention in great detail, it is useful to describe an
example environment in which the invention can be implemented. In the
broadest sense, the invention can be implçm~nted in any wireless communication
network where channel or frequency band selection needs to be done. One
example of such a wireless communication network is a cellular telephone
communication network, an example of which is the well known advanced
mobile phone system (AMPS). Another example is the personal cornmunication
system cellular net.~,vork.
FIG. I is a block diagram illustrating a typical wireless
telecornmunication network 100 that can serve as an example environment of the
invention. The telecomrnunication network 100 includes cell sites 102, cell sitecontrollers 104, mobile switches 106, home location register 108, radio trunk
groups 111, and sign~ling links 112. Subscribers communicate via this network
100 using mobile telephone termin~ 1 10 (e.g., cellular phones in this
environment) which preferably interface to the network 100 via an air in~erf~ce
114.
Each cell site 102 includes a radio transmitter that covers a particular area
for that cell site 102. The call coverage area for a given cell site 102is the area
in which a subscriber can access the telecommunications network 100 by that
particular cell site 102.
Associated with one or more cell sites 102is a cell site controller 104
(sometimes referred to as a base station controller). One function of the cell site
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controller 104 is to ~let~nnine the call coverage area for each associated cell site
102. In addition to det~rmining coverage area, the cell site controllers 104 areresponsible for monitoring each of their associated cell sites 102. Cell site
controllers 104 also calculate the resource capacity for the network elements they
control such as associated cell sites 102 and trunk groups 111 (described below).
The group including the cell site controller and its associated cell sites 102
is usually referred to a mobile subscriber group (MSG). Several MSGs
connected to a mobile switch 106 are referred to as a base station subsystem.
A group of one or more cell site controllers 104 is controlled and
10 monitored by mobile switch 106 (sometimes referred to as a mobile services
switching center, or MSC). Mobile switch 106 is a switch or a switching system
that provides communication paths to other networks. For example, mobile
switch 106 can communicate with another telecommunications network such as
a public switched telephone network (PSTN).
Mobile switch 106 can also be used to calculate resource capacity and
HDSIA data for the associated cell site controllers 104. Mobile switch 106 can
also include a visitor location register (VLR) to store information mobile
subscribers that roam into its coverage area.
The entire telecomrnunications network 100 is monitored and controlled
by home location register 108. Home location register 108 is a database that
contains information concerning the mobile subscriber such as their access
capabilities, subscribed services and supplementary services. Home location
register 108 can determine the coverage area for each of the cell sites 102 in the
entire network 100, keep track of traffic in the telecommunications network 100,and m~int~in a record of the status of telecommunications network 100. The
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home loeation register 108 can also caleulate resource capacity and HDSIA data
for the mobile switches 106 that it controls.
Communication between the various network elements deseribed above
occursovert~unkgroups 111 and~ign~linplinks 112. Trunkgroups 111 transmit
5 call traffic between the various elements of the teleeommunications network 100.
Each trunk group 111 can transmit one or more calls over one or more trunk lines(not shown).
The ~ign~linJ links 112 transmit control and status information between
the various network elements of teleeommunications network 100. Control
10 information ineludes cell site configuration such as eoverage area. Status
information includes alarm data as described above. An example of a ~ign~lin~
link 112 is an SS7 (~ign~linp system 7) signaling link.
A subscriber can eommunicate using the teleeommunications network 100
via a mobile phone (or a mobile telephone terrnin~l) such as the mobile phones
15 1 10. The communieation path ean be an air interfaee such as the air interfaces
114. When a subscriber makes a call, a connection is established between the
subscriber's particular mobile phone 110 and a particular cell site 102 via air
interfaee 114.
For AMPS eellular networks, the speetrum alloeated by the FCC has a
20 bandwidth of 50MHz. This speetrum is divided into two equal parts, referred to
as system A and system B. System A and B each have an allocation of 416
frequency pairs with 30kHz channel spaeing.
The present invention is deseribed in terms of this example environment.
Specifically, the invention is described in terms of an AMPS network having a
25 spectrum divided into two sides, or bands: the A-side and the B-side. Description
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in these terms is provided for convenience and ease of description only. It is not
intt~ntled that the invention be limited to application in this example environment.
In fact, after reading the following description, it will become al~palellt to aperson skilled in the relevant art how to implement the invention in alternative5 environments such as an AMPS environment having more than two bands, the
PCS environment, or in other communication networks.
3. Embodiments of ~he Invention
As stated above, both the AMPS and the PCS provide a spectrum that is
divided into bands (referred to as A-side and B-side for current AMPS networks).10 Each band is handled by a design~tecl service provider. The subscriber's mobile
phone 110 is configured to access the subscriber's desired service provider on one
side ofthe spectrum. Thus, if the subscriber's desired service provider is on the
A-side of the spectrum for example, that subscriber's mobile phone I 10 attemptsto connect to the A-side of the spectrum regardless of the area from which the call
15 is made.
However, where the subscriber's service provider is a reseller, a
subscriber's desired service provider may change from one area to the next.
Thus, when that subscriber roams to a different geographic area, he or she may
need to access a different side of the spectrum to reach his or her desired service
20 provider.
Traditionally, this had been done by requiring the subscriber to
'reprogram' his or her mobile phone 1 10 to access the other side of the spectrum.
Thus, for example, with a conventional network, when a subscriber whose home
carrier (desired service provider) is on the A-side roams to an area where the
25 desired service provider is on the B-side, the subscriber must reprogram his or her
mobile phone 110. If the subscriber does not reprogram mobile phone 110,
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service will be provided by a carrier other than the desired service provider, and
perhaps at substantially increased rates. This other carrier is referred to as a"foreign service provider" in this document.
According to the invention, a system and method are provided for
5 automatically reprogr~mming the subscriber's mobile phone 110 to access the
correct side of the spectrum, regardless of whether the correct side is different
from the side on which the subscriber's usual design~te~l service provider
operates. In this section of the document, several alternative embodiments are
presented and described.
FIG. 2 is an operational flow diagram illustrating a process according to
one embodiment ofthe invention by which a subscriber's desired service provider
is accessed regardless of the side of the spectrum on which the desired service
provider is operating. In a step 204, the subscriber initiates a service request of
the communications network (e.g., of network 100). This request can be initiated15 by subscriber turning on mobile phone 1 10, origin~ting a phone call using mobile
phone 110, entering a new geographic area, or other like action.
In a step 208, mobile telephone 110 requests access on the subscriber's
home side of the spectrum. That is, the request is made on the side of the
spectrum on which the subscriber's phone normally operates when the subscriber
20 is in his or her norrnal, or home, geographic area. This request results in a service
request to the service provider which provides service on that side of the spectrum
in the subscriber's current geographic area. This service provider is referred to
as a "default service provider" throughout this document.
Depending on the arrangements that the reseller has with the default
25 service provider, the default service provider may or may not be the desired
service provider for the geographic area from which subscriber is placing this
call.
. .
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In a step 212, it is det~rmin~d whether the default service provider is the
subscriber's desired service provider. In one embodiment, this is accomplished
by determining whether the desired service provider is operating on the side of
the spectrum on which service was requested in the current geographic area.
S This can be accomplished by using the subscriber's ID as a key to lookup service
provider information in a database
In another embodiment, this is accomplished by determining the
identification of the default service provider and determining whether the default
service provider is a desired service provider. One way of doing this is by doing
10 a lookup using a list of desired service providers for the subscriber.
If the default service provider is the subscriber's desired service provider,
service is granted as illustrated by a step 216 and normal registration actions are
taken by home location register 108.
If, on the other hand, the default service provider is not the subscriber's
15 desired service provider, it is ~etennin~d whether a desired service provider exists
on another side of the spectrum. This is illustrated by a step 220. If a desiredservice provider is not available on another side of the spectrum, access is granted
to the default service provider and normal registration actions are taken by thehome location register 108.
If, however, a desired service provider is available on another side of the
spectrum in the subscribers current geographic area, a message is sent to the
subscriber instructing him or her to change to the side of the spectrum on whichthe desired service provider is operating. This is illustrated by a step 228. In one
embodiment of step 228, the subscriber is required to reprogram the phone to
operate on the desired side of the spectrum. In this embodiment, the subscriber
_ _
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12
can be notified using audio, alphanurneric text (such as textual short message) or
other technique to inform the subscriber of the correct side of the spectrum.
In another embodiment of step 228, the process is automated so that the
subscriber need not take any specific action. In one embodiment of this
5 automated process, mobile phone I 10 is instructed to change to the side of the
spectrum on which the desired service provider is operating. This can be
accomplished by sending an instruction, command or other message to the
subscriber's mobile phone 110 instructing mobile phone 110 to switch sides.
This can be accomplished using CDMA (Code Division Multiple Access) over-
10 the-air activation, TDMA (Time Division Multple Access) over-the-air activation,
GSM USSD (Group Speciale Mobile Unstructured Supplementary Service Data),
or short message teleadmin techniques, as well as by other techniques.
In response to the instruction sent in step 228, subscriber's mobile phone
1 10 resets the default service provider (i.e., the default side of the spectrum) to
15 the side on which the desired service provider is available. This occurs in a step
232. Where required, mobile phone 110 initiates a new access through the
available desired service provider.
In one embodiment, the process described above is accomplished using
additional information available at the subscriber's home HLR. In this
20 embodiment, information such as desired carriers, mobile switch IDs, spectrumindicators and other information can be used to determine whether the default
carrier is a desired service provider and, if not, whether a desired service provider
is available in the geographic area.
In one embodiment, when the subscriber initiates service in a foreign
25 geographic area (i.e., a geographic area other than the subscriber's home
geographic area), a notification message is sent to the home location register 108
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serving the subscriber's home area. Included in this message is an identification
of the service provider available to serve the subscriber in the current geographic
area. In one embodiment, this identification is made using a mobile switch ID orother indication that can be used to clet~.nnine the service provider identification.
Home location register 108 determines whether this available service provider
is a desired service provider. In one embodiment, this is accomplished by
comparing this identification to a list of desired service providers.
Where the default service provider is not a desired service provider, home
location register 108 determines whether there is a desired service provider in that
10 geographic area and, if so, the side of the spectrum on which it operates. In one
embodiment, this is accomplished by a simple table lookup.
The process used by home location register 108 in these embodiments is
now described with reference to FIG. 3. In a step 304, the mobile switch
identification is detennined from the message. In one embodiment this is
15 accomplished by retrieving the record cont~ining the mobile switch ID from the
message. In one embodiment, if the record is not found, an error condition exists
and the process halts.
In a step 308, the mobile switch ID is used to determine whether the
service provider is a desired service provider. In one embodiment, this is
20 acc~ mplichtod by ~ t~rrnining the identity of the default service provider from the
mobile switch ID and then comparing this identity with the desired service
provider (or by simply comparing ID's). If the service provider identified by the
mobile switch ID is a desired service provider, then the process is completed and
registration can continue as normal as illustrated by step 312.
25If, the identified service provider is not a desired service provider, home
location register 108 checks its database to determine whether a service provider
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on another side of the spectrum is a desired service provider. This is illustrated
by a step 316. In an embodiment where there are only two sides to the spectrum
and only one service provider per side, this can be a simple boolean indicator of
whether the other service provider is a desired service provider. Where there is5 a desired service provider on another side of the spectrum, the subscriber (or the
subscriber's mobile phone 110 in an automated embodiment), is notified to
change to that side of the spectrum.
If a desired service provider does not exist in that geographic area, a
notification is sent to the subscriber to indicate this. The notification process can
10 be accomplished according to a number of different embodiments. In one
embodiment, a call is placed to the subscriber notifying him or her that only a
foreign service provider is available and this may result in additional charges for
the service. This can be done using a voice call that plays scripts to the
subscriber stating that the only service provider is a foreign service provider, or
15 by using alph~nllmf ric signals that can be displayed on an alphanumeric display
on mobile telephone 110. Alternatively, a command can be sent to mobile
telephone 110 to provide an indication via mobile phone 110 that the only service
provider available is a foreign service provider. This indication can include, for
example, an indicator light, a display flag on a display screen of mobile phone
20 110, a specific tone, or other indication.
In another embodiment, the notification process can include instructions
on how to register with the foreign service provider. In this case, the subscriber
has the choice of not making any calls, paying higher prices to a foreign service
provider, or registering with the foreign service provider before making a call.
Although the process is described above as being performed by the home
location register 108, it could easily be performed by a physically or logicallyseparate entity. In these embodiments, the separate entity may use data already
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existing in home location register 208 to avoid unnecessary duplication and
maintenance of data.
In other alternative embodiments, determination and selection of the
desired service provider is accomplished by a mobile phone search of the
5 spectrum. FIG. 4 is a diagram illustrating a process by which this selection is
made according to one embodiment. In a step 404, the subscriber initates a
service request of the communications network (e.g., of network 100~. This
request can be initiated by subscriber turning on mobile phone 110, origin~tin~
a phone call using mobile phone 110, entering a new geographic area, or other
10 like action.
In a step 408, mobile telephone 110 requests access with the default
wireless service provider. In other words, mobile telephone requests access withthe wireless service provider that is normally used by the subscriber in the
subscriber's home territory. Depending on the arrangements that the reseller has15 with the default service provider, the default service provider may or may not be
the desired service provider for the geographic area from which subscriber is
placing this call.
In a step 412, it is determined whether the default service provider is the
subscriber's desired service provider. If the default service provider is the
20 subscriber's desired service provider, service is granted and normal registration
actions are taken by home location register 108. This is illustrated by a step 424.
If, on the other hand, the default service provider is not the subscriber's
desired service provider, mobile telephone 110 automatically changes to a
different side ofthe spectrum and the process conducted in steps 408 and 412 is
25 repeated. This time, in step 408, the request is not made to the default, butinstead is made to the service provider on the current side of the spectrum. This
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process is repeated for each side of the spectrum until a side is accessed on which
a desired service provider operates. This is illustrated by steps 416 and 420 and
flow line 462.
If there is no available desired service provider after all sides of the
S spectrum are investigated, in a step 428 the subscriber is notified that only foreign
service providers are available. This process is similar to that described abovewith reference to FIG. 2, steps 22~ and 232.
3. Conclusion
~hile various embodiments of the present invention have been described
10 above, it should be understood that they have been presented by way of example
only, and not limitation. Thus, the breadth and scope of the present invention
should not be limited by any of the above-described exemplary embodiments, but
should be defined only in accordance with the following claims and their
equivalents.
