Title of Invention

"METHOD AND SYSTEM FOR USE IN REDUCING COST ASSOCIATED WITH LOST CONNECTIONS IN WIRELESS COMMUNICATION"

Abstract The present embodiments provides for notifying a remote communication device (124/126) when a local wireless device (122) loses its wireless link (112). A method detects when a wireless connection (112) is lost with a first communication device (122) identifies a second communication device (124, 126) that is communicating with the first device, and notifies the second device of the lost link. The notification of the lost link is supplied while the method provides batch communications. Voice communications, where a remote device is notified when a local device loses its wireless connection, can be provided. The second device can be determined by querying a server (150). The notifying can include forwarding an in- band tone, and/or generating a real time protocol packet. The loss of the link is detected through a radio access network (134), a packet control function (132), and/or a mobile switching center (136).
Full Text

FIELD OF THE INVENTION
[0001] The present embodiments relate generally to mobile communication
systems, and more particularly to mobile communication systems that monitor lost
wireless connections.
BACKGROUND OF THE INVENTION
[0002] The use of wireless communication is growing exponentially. As a result,
the amount of time an individual spends wirelessly communicating is also drastically
increasing. Therefore, the costs associated with lost connections between parties are
additionally increasing.
[0003] Parties using wireless communication sometimes lose their wireless
connection. Other parties participating in the communication are often at least
temporarily unaware of the lost connection. As a result, significant amounts of time
are often wasted by users waiting for responses and/or trying to deterrnine if another
party to a communication has been lost. Users often may continue to talk or
communicate information even though another party to the communication has been
lost.
[0004] This wasted time can be very frustrating to users and can significantly
degrade a user's experience.
BRIEF DESCRIPTION OF THE. ACCOMPANYING DRAWINGS
[0005] The above needs are at least partially met through provisions of methods,
apparatuses, and/or systems for use in reducing the costs associated with lost wireless
connections, as described in the following detailed description, particularly when
studied in conjunction with the drawings, wherein:
[0006] FIG. 1 depicts a simplified block diagram of a communication system or
network according to some present embodiments;

[0007] FIG. 2 depicts a simplified graphical representation of communication
logic flow between components of the system of FIG. 1;
[0008] FIG. 3 depicts a more detailed graphical representation of communication
logic flow according to some embodiments for a notification step in the process of
FIG. 2;
. [0009] FIG. 4 depicts a simplified flow diagram of a process according to some
embodiments where a radio frequency (RF) link loss is detected by a packet control
function (PCF) and the PCF generates a notification;
[0010] FIG. 5 depicts a simplified flow diagram of a process for detecting a loss
of one or more parties to a group communication and the notifying one or more other
parties participating in the group communication;
[0011] FIG. 6 depicts a simplified block diagram of a communication system or
network providing voice communication over a voice path;
[0012] FIG. 7 depicts a simplified graphical representation of time-line logic
flow of the signaling between components of the communication system according to
voice communication systems without the implementation of the present
embodiments;
[0013] FIG. 8 depicts a simplified graphical representation of time-line logic
flow of the signaling between components of the communication system providing
notification of lost wireless links according to the present embodiments;
[0014] FIG. 9 depicts a simplified graphical representation of communication
logic flow between components of a system, such as the system of FIG. 6, when
providing voice communications over voice communication paths where a mobile-
switching center (MSC) provides the notification of a lost wireless link;
[0015] FIG. 10 depicts a simplified graphical representation of communication
logic flow 1010 between components of a system, such as the system of FIG. 6, when
providing voice communications over voice communication paths where a radio
access network (RAN) provides the notification of a lost wireless link; and

[0016] FIG. 11 depicts a simplified flow diagram of a process for use in
determining whether a system or network is implementing the present embodiments
to detect wireless link loss and to notify one or more other users of the loss.
[0017] Corresponding reference characters indicate corresponding components
throughout the several views of the drawings. Skilled artisans will appreciate that
elements in the figures are illustrated for simplicity and clarity and have not
necessarily been drawn to scale. For example, the dimensions of some of the
elements in the figures may be exaggerated relative to other elements to help to
improve understanding of various embodiments of the present invention. Also,
common but well-understood elements that are useful or necessary in a commercially
feasible embodiment are often not depicted in order to facilitate a less obstructed view
of these various embodiments of the present invention. It will also be understood that
the terms and expressions used herein have the ordinary meaning as is accorded to
such terms and expressions with respect to their corresponding respective areas of
inquiry and study except where specific meanings have otherwise been set forth
herein.
DETAILED DESCRIPTION OF THE INVENTION
[0018] The present embodiments provide apparatuses, methods and systems for
use in notifying a second, remote communication device when a first, local wireless
communication device loses its wireless communication connection or link. Without
this notification, the user of the second, remote communication device is unaware that
the first communication device has lost its link, and the second user may unknowingly
continue to try and communicate and/or wait for a reply for an extended period of
time. This is a waste of the second user's time and can be very frustrating. Therefore,
the present embodiments notify a remote user when a local user loses his/her wireless
link. The quick notification provided by the present embodiments greatly improves
users' experiences and increases users' satisfaction.
[0019] Some embodiments provide methods for use in providing wireless
communication. These methods monitor local wireless communication connections

and detect when a wireless communication connection is lost with a first
communication device. A second communication device is determined with which
the first communication device was communicating, and the method notifies the
second communication device of the lost wireless connection. In some
implementations, the second communication device is determined by querying a
server for the second communication device. The method for notifying can, in some
embodiments, include forwarding an in-band tone to the second communication
device and/or generating and forwarding a real time protocol (RTP) packet, hi some
embodiments, the loss of the wireless link is detected through a radio access network
(RAN), a packet control function (PCF), and/or a mobile switching center (MSC).
[0020] Some further embodiments provide a method for use in notifying a user of
a loss of a wireless connection. These methods establish a communication connection
between a first communication device and a second communication device over a
communication network, where the first communication device wirelessly
communicates with the second communication device over at least a first wireless
link. When a loss of the first wireless link with the first communication device is
detected, the methods notify the second communication device of the loss of the
connection with the first communication device. The detection of the loss can
comprise detecting the loss of the wireless link through a PCF, and the notification
can comprise generating a notification from the PCF, and injecting the notification
onto the communication connection directed to the second communication device. In
some implementations, the PCF notifies a server of the detected loss of the wireless
link with the first communication device, and receives an identification of the second
communication device from the server such that the PCF accurately forwards the
notification to the second communication device.
[0021] Systems for use in providing wireless communication are provided in
some embodiments. These systems preferably comprise a base station that wirelessly
communicates with a first communication device over a wireless link, a radio access
network (RAN) coupled with the base station, and a second communication device
communicationally coupled with the first communication device through at least the

RAN. The RAN detects a loss of the wireless link and generates a notification and
forwards the notification to the second communication device notifying the second
communication device that the wireless link has been lost. In some implementations,
the RAN comprises a PCF that detects the loss of the wireless link. The system can
further include a packet data serving node (PDSN) coupled with the RAN and further
coupled with a distributed network, such that the second communication device is
communicationally coupled with the first communication device through at least the
RAN, PDSN and the distributed network.
[0022] The operation of the present embodiments enhances user experience and
significantly reduces wasted time when a first user is wirelessly communicating with
a second user and the first user loses the wireless link. In existing communication
networks, the loss of a first party on a wireless connection leaves a second party in
limbo with the second party unaware that the first party has lost the wireless
connection for some period of time. This is particularly relevant when the lost
communication device is unable to signal a loss and/or drop from the communication
link.
[0023] For example, if the first party is communicating over a wireless link to a
second party communicating over a wireless or wired connection, and the first party
loses the wireless link, the second party is unaware that the first party has lost the
wireless link. Some wireless devices can signal the local user directly when the
wireless device loses the connection, however, the other remote party or parties to the
communication are unaware of the loss. The second or remote user is left unnotified
and waiting for further communication. The second user may wait five, eight, ten
seconds or more before realizing that the first party is no longer on the line. This is
particularly apparent at the time the second party is talking or sending a
communication when the first party loses the connection. The second party may
continue to talk for several seconds (e.g., ten seconds or longer) before realizing that
the first user is no longer present on the connection. This can be a significant waste of
time, and is particularly frustrating. It is often difficult to determine what was
communicated and what the first user did not receive.

[0024] The present embodiments advantageously address this lack of notification
by signaling and/or notifying a user when another party to a communication loses or
is dropped from a wireless connection. The loss can occur because of a lost wireless
connection (e.g., a lost radio frequency (RF) connection interference, failed handoff
due for example from resource unavailability, etc.), a loss due to a power failure (e.g.,
a mobile phone runs out of battery power), damage to a mobile device (e.g., a user
drops his/her mobile phone), and other such occurrences where a connection is lost.
[0025] In some communication systems and/or networks, the systems distinguish
between data communications versus voice communications, and/or dispatch
communications versus telephony-styled communications. Typically, voice
communications and/or services are real-time applications. Further, these systems
attempt to provide equal service to all users, regardless of locations relative to
transmission stations, such as base transceiver stations (BTS). Further, because voice
communications typically do not communicate large amounts of data, communication
systems typically allocate relatively low or modest data rates while still providing
high-quality voice service.
[0026] Alternatively, systems providing dispatch or direct connect
communications attempt to maximize the amount of data communicated through the •
system. Typically, users have different data rate requirements. In maximizing the
data rates, systems attempt to allocate each user with the maximum data rate that the
user can accept. This allocation is typically also limited by the communication
channel, the interference on the channel, the amount of data bandwidth a user needs
and other such conditions. Data or dispatch communications can also communicate
voice data. For example, data communications include push-to-talk communications
that are treated as data communications avoiding the need to dedicate communication
links, voice over Internet, and other such communications. Employing data
communications with some voice data allows the voice to be broken up and
communicated over optimal routing and recombined to produce the output voice
message. Further, data communications typically are implemented through shared

resources, where packets can be communicated over a variety of different connections
and recombined before final transmission to the intended recipient.
[0027] Because of the different structures and applications in communicating
dispatch or direct connect communications versus voice communications, many of the
present embodiments, in some implementations, distinguish between data
communications and voice communications.
[0028] Generally, in implementing a dispatch communication, a first party knows
a private identifier of a second party, and uses the identifier to make a dispatch call to
the second party. Once the first party initiates a dispatch call, the communication
system rapidly sets up the call, and sends a message to the first party's communication
device. Upon receiving the message, the first party's radio generates an audible alert
to let the first party know when to begin speaking and/or communicate data. In
alternative embodiments, the speaker may be permitted to begin speaking prior to
receiving this feedback. The second party's communication device receives the voice
or data signal and plays or make the data available for the second party to receive,
without the second party necessarily having to take any action.
[0029] The nature of dispatch communications, however, makes if very difficult
for one party to determine if and when the party has lost his/her wireless connection.
Because there can be long silences between a first party transmitting a communication
and a second party replying to the first party, the first party is unaware for potentially
long periods of time that the second user has lost the connection. Further, dispatch
communications are typically implemented over half-duplex channels. As such, only
one user communicates at a time, such that a speaking user is unaware that the other
party to the communication has been lost from the connection. Therefore, the
speaking user may continue to speak without knowing the other user is missing and
may wait an excessive amount of time before determining that the other user is no
longer on the connection.
[0030] The present embodiments provide methods and systems for identifying
when one or more parties of a communication are dropped or lose their wireless
connection. The methods and systems quickly notify the other party or parties of the

communication that a user lost his/her connection. This saves the party that has not
been dropped from waiting relatively long periods of time before determining that the
other user is no longer on the line.
[0031] FIG. 1 depicts a simplified block diagram of a communication system or
network 110 according to some present embodiments, where a. first wireless device or
mobile station 122 communicates over the network 110 through a dispatch
communication (e.g., push-to-talk (PPT)) with a second wireless device 124 and/or
wired device 126. The wireless devices can be substantially any wireless device
capable of employing dispatch communications, such as wireless phones, pagers,
personal digital assistants, desktop computers, laptop computers, and other such
wireless communication devices. Often dispatch calls are mobile-to-mobile (M-M)
communications, however, the present embodiments can be applied to mobile-to-
wired or land calls (M-L) as well as land-to-mobile calls (L-M). Further, the present
embodiments can be utilized with any relevant wireless communication techniques
including, but not limited to code division multiple access (CDMA), CDMA2000,
global system for mobile communications (GSM), general packet radio service
(GPRS), universal mobile telecommunications systems (UMTS) (including third
generation 3G UMTS), and other such wireless communication techniques.
[0032] The first wireless device 122 transmits and receives communications over
a wireless link 112 with a base station, such as a base transceiver station (BTS) 130
and/or enhanced base transceiver system (EBTS). The BTS forwards and receives
data to and from a packet control function (PCF) 132. The BTS 130 and/or PCF 132
are, in some embodiments, incorporated within a radio access network (RAN) 134.
The RAN provides control and routing of communications to and from the wireless
devices, e.g., wireless device 122.
[0033] The RAN 134 couples with a mobile switching center (MSC) 136. The
MSC switches communications (e.g., telephone calls) within the system or network
110 and also tp the public switched telephone network (PSTN) 160 allowing access to
wired communication devices 126 and other network components. The MSC 136

interfaces with the RAN 134 to perform call setup and release, and various functions
such as call processing and supplementary service related functions.
[0034] The PCF 132 of the RAN further couples with and forwards packets of
data to a packet data serving node (PDSN) 138. The PDSN provides access and
gateway functions between the wireless system and a public data network (PDN) 140,
such as an intranet, the Internet and other such distributed networks 140, so that the
first mobile communication device 122 can communicate voice and/or data content
with other communication devices of the network (e.g., second mobile device 124
and/or wired device 126), to access data and/or content on the public data network,
perform other activity such as email, and other similar functions and operations. In
some implementations, the system includes and/or cooperates with conferencing
devices, bridges and/or services 170. These conferencing bridges allow parties to
establish conference calls by the users accessing the bridge 170. Typically, the users
122,124,126 access the conference bridge 170 through a distributed network 140 or
160.
[0035] In operation, the RAN 134 monitors the wireless link 112 to ensure
accurate communication. For example, the RAN can direct the wireless device 122 to
communicate with other BTSs, increase and/or decrease transmission power levels,
and provide other control information with the wireless device. In some
embodiments, the RAN can further detect a loss of the wireless device 122 and/or loss
of the wireless link 112. Upon the detection of a loss of the wireless device 122, the
RAN 134 notifies the PCF 132 to initiate a notification of other users and/or devices
currently communicating with the first wireless device, as fully described below.
[0036] Still referring to FIG. 1, in some embodiments, the system or network 110
can additionally and/or alternatively provide communication paths through a base
station controller (BSC) 180. A third wireless device or mobile station 128 can
communicates with a second wireless device 124 and/or wired device 126 through the
BSC 180. The third wireless device 128 transmits and receives communications over
a wireless link 112 with a BTS 130. The BTS couples with the BSC 180. The BSC
ensures packets are received and forwarded in order, essentially controlling the

retransmission aspect of the wireless radio link 112 between the third wireless device
128 and the BTS 130. Further, the BSC 180 includes a PCF 132 and a selector
distributor unit (SDU) 182. The SDU combines signals when a single wireless device
128 can be received by multiple BTSs. The PCF 132 additionally provides some
buffering of packet data for the SDU 182.
[0037] The BSC 180 is typically coupled with an MSC 136. As described above,
the MSC provides switching of calls over the (PSTN) 160 and/or other networks. The
MSC 136 interfaces with the BSC 180 to perform call setup and release, and various
functions such as call processing and supplementary service related functions. The
BSC 180 can, in some implementations, further couple with and forwards packets of
data to a PDSN 138 to establish communication over the network 140. The PCF 134
of the BSC monitors the wireless link with the third wireless device 128. In the event
that the PCF detects a loss of the first wireless device, the PCF notifies other devices
currently communicating with the first wireless device.
[0038] In some embodiments, the PDSN 138 adds addressing header information
so that the packets can be transmitted over the network 140. If the target mobile
communication device (e.g., second wireless device 124) is in a different region of the
network 110, the PDSN can forward the data packets over the network to a second
PDSN (not shown) to remove the header addressing information and forward the
packets to the target wireless device 124.
[0039] The communication network 110 allows for data or dispatch
communications between devices of the network. For example, the first wireless
device 122 can communicate with the second wireless device 124 through push-to-
talk (PTT) capabilities, Voice-over-IP capabilities and other batch and/or data path
communications. Utilizing PTT, the system receives a request, for example, for the
first wireless 122 to establish a data communication between the first and second
wireless devices 122,124. As discussed above, the first user, for example, identifies
the second user and depresses a button on the first wireless device to activate or
initiate communication. Upon establishing a connection with the second device, the
system signals the first device (e.g., causing the first wireless device to generate an

audible tone, generate a packet containing the audible coding of beep or other tone,
generate a display, illuminate a light or other such signal) that the connection is
established. The first and second users can then alternately verbally communicate
with one another. Typically, only one communication device communicates at a
given time, and communication between the two wireless devices is achieved by
alternating the control of the connection between the two wireless devices. Further,
the system typically provides a half duplex channel where communicating devices
share the channel with one device controlling the channel at a time.
[0040] In some preferred embodiments, the RAN 134 and/or PCF 132 monitor
the wireless link of the associated wireless device. For example, the RAN 134 or PCF
132 monitor the wireless link 112 with the first wireless device 122 and/or the PCF
132 monitors the link with the third wireless device 128. If the RAN 134 and/or PCF
132 detects that the link 112 is no longer active the PCF generates a notification that
the first wireless device 122 (or third device 128) no longer has an active link. In
some implementations, the PCF generates a notification that is forwarded to a second
user currently communicating with the first user (e.g., user communicating through
wireless device 124). The notification indicates that the first wireless device 122 lost
the wireless connection 112. For example, the PCF 132 can generate and inject a
brief real time protocol (RTP) packet into the communication with the second device.
The real time protocol packet notifies the second user that the first user lost the
wireless link 112. The notification can cause the second communication device 124
to generate an audible tone, to display a message, to illuminate or flash a light, can be
a generated packet containing an audible coding of a tone, and/or other similar
functions that notifies the second user of the lost link. In some embodiments, the PCF
additionally and/or alternatively notifies a server 150 of the communication link loss.
The server can then inject and/or fan out the notification to one or more users
communicating with the lost wireless device, and/or other components of the system.
[0041] By having the RAN 134 and/or PCF 132 monitor the wireless link 112,
the system 110 rapidly detects the loss. As a result, the second user is quickly notified
that the first user lost the connection and the second user can take appropriate steps

(e.g., try and reconnect, disconnect, and other similar functions), without having to
wait extended periods of time trying to determine whether or not the first user is still
connected.
[0042] FIG. 2 depicts a simplified graphical representation of communication
logic flow 210 between components of the system 110. Following the cooperating of
the first and second communication devices, and once the initiating party (e.g., first
mobile station (MS) 122) receives an indication that the target party (e.g., second
mobile station (MS2) 124) is connected and available to receive audio data, the RAN
134 monitors the wireless link 112 in step 230. Once the RAN identifies a loss of the
link, the RAN issues a release order in step 232 to the first MS 122.
[0043] A lost or dropped connection can be identified by numerous conditions,
lack of signals and/or data, and other such information including, but not limited to,
failing to receive good frames for a predefined period of time on a reverse link, failing
to receive reverse dedicated pilot communications, power control bits, channel quality
information, received signals with errors exceeding a threshold, receiving insufficient
frames and/or bad frames for a period of time, if a signal or signals received from the
wireless device are below a certain quality and/or below a certain quality for a
predefined period, and other such indications and/or combinations of indications.
Generally, if the system fails to receive information informing the system that the
wireless device is active for a predefined and/or unreasonably long period of time, the
RAN and/or PCF identify the link as an RF loss. RF loss can occur for several other
reasons. For example, a disconnect may occur when a call or the resources being
used is preempted or the call is dropped because of resource unavailability (typically
these disconnects occur for lower priority calls), a call might also be dropped if one of
the communication devices has a limited time of operation (e.g., a user is calling with,
a prepaid phone and the minutes run out), and other such disconnects.
[0044] In step 234, the RAN generates a clear request notifying the MSC 136 of
the link failure. In step 236, the RAN generates an A9-Release-A8 message to the
PCF 132 Morming the PCF of the failure. In step 240, the PCF 132 generates and
injects the loss notification to the second mobile station MS2, at which point the

second user is aware of the link loss and no longer waits to determine if the first user
is still on line. The notification can be generated through a number of different
techniques. For example, the PCF can generate and inject an audio signal and/or
message, such as an RTP packet to the other communication device (e.g., device 124
and/or 126), the PCF can generate a section initiation protocol (SIP) messaging,
and/or the PCF can generate other similar notifications or combination of notifications
as are known in the art.
[0045] In step 242, the PCF 132 sends an Al 1 registration request message with
a stop airlink request to the PDSN 138, and request the session be shifted to dormant.
The PDSN updates the system data accordingly. In step 244, the MSC 136 upon
receipt of the clear request from the RAN 134 issues a clear command to the RAN. In
step 250, the PDSN 138 replies to the registration request with an Al 1 registration
reply message to the PCF 132. In step 252, the PCF in turn issues an A9-release-A8-
complete acknowledgement to the RAN 134. In step 254, the RAN generates and
forwards a clear complete acknowledgement to the MSC 136.
[0046] In the implementation of the logic flow 210 of FIG. 2, the second mobile
station 124, and thus the second user, are notified relatively early in the process 210.
This saves the second user a significant amount of time, reduces the second user's
frustration, allows for the saving of network resources, and other benefits as described
above and more fully below. Further, the present embodiments can be implemented
without changes to standards and standard communications between system
components. In some preferred embodiments, the equipment failure A9-Release-A8
signal is interpreted as the unexpected call loss, such that the PCF initiates the
notification to the other user(s) of the lost connection.
[0047] FIG. 3 depicts a more detailed graphical representation of communication
logic flow 310 according to some embodiments for the notification in step 240 of
FIG. 2, where the PCF injects the notification to a remote user indicating the loss of
the wireless link with the local user. The RAN detects the link loss with the local
wireless communication device (e.g., device 122) in step 230 of FIG. 2, and generates
an equipment failure notice to the PCF 132 (e.g., an A9-Release-A8 message)

informing the PCF of the failure in step 236. Referring to FIG. 3, in step 322, the
PCF generates a loss notification that is directed to the target, remote communication
device (e.g., wired device 126), and forwards the notification to be delivered to the
remote device. The notification can, as described above, be a tone, a text message, a
command to cause the remote device to generate a tone or light up. In some
embodiments, the PCF can utilize a prepared or predefined RTP audio file to provide
the RF link loss indication to the remote device. The RTP packet or packets can be
forwarded to the PDSN 138.
[0048] In step 324, the PDSN 13 8 receives the notification from the PCF, and
formats and communicates the notification over the distributed network 140 to be
received by a remote second PDSN 312. In step 326, the remote PDSN converts the
formatted notification and forwards the notification as an A10 communication to a
remote second PCF 314. In step 330, the remote PCF forwards the notification to the
remote communication device 126. In step 332, the remote communication device
notifies the second user, for example, by generating an audible tone as defined by the
RTP packet(s).
[0049] In some implementations, the RAN 134 and/or the PCF 132 detects the
loss of the wireless link 112 with the first communication device 122. Often,
however, the PCF is unaware or does not know the identity of the second
communication device or how to route the notification to the second communication
device. In some implementations, the PCF attempts to determine or infer the remote
user through the types of communication, addressing within the communications (e.g.,
IP addressing) and other such data. Additionally and/or alternatively in some
embodiments, the PCF 132 upon detection of the lost link, communicates with a
server 150 to identify the second communication device.
[0050] The server 150 can be identified according to types of communication, the
lost user, addressing within the communications, look up tables, and other such
information. In some embodiments, the PCF 132 and/or RAN 134 communicate with
a specific designated server (e.g., a first network server because that is the server
specified by a specific wireless communication carrier). In other embodiments, the

PCF/RAN identifies the server based the type of communication, on the user lost,
and/or addressing within the communications (e.g., IP addressing and/or other such
addressing). For example, in some implementations the PCF/RAN (or other network
component) can store users' IP addresses upon initiation of the communication
connection. The stored IP addresses can be later used if the connection should be lost.
The server can be located with the MSC 134, the PDSN 138, a separate server 150
coupled with the distributed networks 140,160 and configured to communicate with
the PDSN, MSC and/or PCF/RAN and provide call processing flows including
distributing forward voice streams to the communication devices (e.g., one or more
wireless devices employing PTT that can be accessed through different PCF/RANs),
, track user billing and other such services. The servers 150 can be operated by the
system 110 provider, other companies provide wireless communication services (e.g.,
Nortel™, Sprint™, Verison™, ATT™ and other such wireless service providers),
and the like.
[0051] Additionally and/or alternatively, some embodiments employ a
conference bridge 170 to monitor the communication between parties of a
communication. Multiple parties establish communication connections by accessing
the conference bridge 170. The conference bridge can detect that one or more users
have been lost. Once a loss is detected the bridge 170 can use that information to
update the conference status, notify the server 150 and/or MSC 136, notify the other
parties participating in the communication, and/or allow the server or MSC to
generate the notification.
[0052] Still further, in some embodiments, the PCF, RAN and/or server can
further verify that the first wireless device 122 was actually participating in
communication with one or more other parties. Once verified, the PCF and/or RAN
initiate the procedures to notify the one or more other parties that the first wireless
device lost the wireless link 112. Additionally in some embodiments, the system
further determines whether a loss was due to an intentional action, such as a user
ended communication, or the network intentionally dropping the connection (e.g.,
aborting the call, selecting another operating mode, reconnecting to a cell not able to

service the wireless device, preempted call, unavailable resources, prepaid minutes
expire, and other such conditions) or the loss was unintentional.
[0053] FIG. 4 depicts a simplified flow diagram of a process 410 according to
some embodiments where a radio frequency (RF) link loss is detected by a PCF and
the PCF generates a notification. In step 420, the PCF detects the link loss. As
described above, the PCF can directly detect the link loss and/or can be signaled by
the RAN about the loss. In step 422, the PCF determines if the local communication
device was actively participating in a communication (e.g., during a PTT either to or
from the MS, or during a PTT "call"; if a PTT from either party occurred within the
past THOLD seconds, where THOLD may equal, for example, six seconds). If the
local device was not actively participating in a communication, the process 410
terminates. Alternatively, if the local device was participating in a communication,
the process continues to step 424 where the PCF determines if the loss was due to an
intentional or normal connection drop (e.g., call is aborted; another operating mode is
selected; reconnecting to a cell not able to service the wireless device; and other such
actions). If the loss is due to an intentional disconnect, the PCT prevents the
notification to the remote device and terminates the process 410.
[0054] If it is determined in step 424 that the communication loss is not due to an
expected normal disconnect, the process continues to step 426. Losses caused by
unexpected disconnects can be caused by an number of effects and/or conditions such
as the local device passes into a tunnel or other area that blocks wireless signals,
power is lost to the device (e.g., battery is disconnected), the device is damages (e.g.,
user drops the device, or something lands or rolls over the device) and other such
conditions. In step 426, the PCF communicates with a server 150 and/or a local MSC
136 to identify the one or more additional target communication devices actively
participating in the communication with the lost local device. In. step 430, the server
or MSC identifies the one or more target devices. In step 432, the PCF generates a
notification and communicates the notification to the one or more target devices. The
notification can be substantially any relevant notification including, but not limited to,

a session initiation protocol (SEP) message, one or more RTP packets, and other such
notifications.
[0055] The present embodiment additionally allows for the notification of one or
more users losing connections during a group call or conference call with more than
two users. During group calls, the PCF 132 and/or RAN 134 systems associated with
each party of the group call monitors the wireless link of their respective wireless
devices participating in the group call. If a loss is detected, the associated PCF/RAN
generates notifications and injects the notifications to one or more of the users
participating in the communication, hi some embodiments, the PCF/RAN notifies
each of the other participants. For example, the PCF can query a server to identify
each of the parties participating and obtain routing to each of the parties. The PCF
can then generate the notification and inject the notification onto the in-band
communication (e.g., a 250 ms tone).
[0056J In some preferred embodiments, the notification to the one or more
parties is provided so that the notification does not interfere with or. only minimally
interferes with the group call. For example, the notification can be delivered as a text
or display message such that the receiving communication devices display the
notification. Additionally and/or alternatively the notification can cause the receiving
communication devices to generate an audible tone. The tone, however, is typically
low compared with a tone that would be sent to a single user so that the low tone is
non-intrusive on the group call. In some alternative embodiments, the notification is
only forwarded to the originator of the group call, or only the user currently having
control over the group call is notified.
[0057] As is known in the art, typically in group calls using push-to-talk, a user
currently speaking has exclusive rights or "control" of group communication. Some
present embodiments additionally determine when a user is lost if the lost user is the
speaking or controlling user. Once determined that the lost user was the controlling
user, the PCF notifies the MSC that the lost user was the controlling user. The MSC
releases the resources that were allocated to the lost user and further releases the
exclusive control so that the lost user no longer "has the floor" of the group call and

that the group communication is now an "open floor." For example, the MSC can
issue a SIP message releasing control of the group call. This allows another user of
the group to take "control" over the group, for example by selecting a push-to-talk:
button on the communication device.
[0058] FIG. 5 depicts a simplified flow diagram of a process 510 for detecting a
loss of one or more parties to a group communication and the notifying of one or
more other parties participating in the group communication. In step 512, the process
detects that a first user has been dropped from a wireless connection. This detection
can be achieved through a PCF, RAN, and/or through an MSC as described above.
Upon detection of a lost user, the process continues to step 514 where it is determined
and/or verified that the first user was actively participating in communication over the
system. If the first user is not confirmed, the process terminates and does not further
notify any other users. Alternatively, if the first user is confirmed, step 516 is entered
where it is determined if the first user is part of a group communication. If the first
user is not part of a group communication, step 520 is entered where the other user of
the communication is notified. In some embodiments, step 520 is implemented
through a separate process, such as the process 210 as described above and depicted
in FIG. 2.
[0059] If it is determined in step 516 that the first user was part of a group
communication, step 530 is entered where the other users participating in the group
communication are identified. In some embodiments, the PCF queries the MSC to
identify the other users. In step 532, the PCF injects a notification to the other users.
As discussed above, the notification can be implemented by an in-band
communication and/or tone that is directed to each of the other participating users.
For example, the PCF can send audio data, such as an RTP packet to the other users,
and/or SIP messaging. In some embodiments, the process continues to step 534
where a number of other users participating in the group communication are
determined, and the PCF adjusts a volume of the in-band communication according to
the number of remaining users participating in the communication.

[0060] Still referring to FIG. 5, in step 540, the process determines if the lost first
user was the controlling user. For example, the PCF queries the MSC to determine if
the first user was actively identified as the speaking or controlling party. If it is
determined that the first user was not controlling, the process 510 terminates.
Alternatively, if it is determined that the first user was the controller part, step 542 is
entered where the MSC releases the first user's control, for example, by issuing an ,
SEP message releasing control of the group call.
[0061] The present embodiments can similarly be operated with desktop dispatch
and/or data communications. The present embodiments are further capable of
identifying a loss of the connection with the desktop, for example, desktops using a
digital subscriber line for data communications. Upon the detection of the lost
connection, the other one or more parties of the communication are notified of the
loss such that the other one or more parties do not have to waste time trying to
determine whether the desktop is still connected.
[0062] In the situation when a lost desktop participating in a wireless dispatch
communication is the speaking or the controlling communication device, no end of
the dispatch message is received from the desktop device. In some embodiments, the
PCF 132 and/or RAN 134 monitor the wireless connection. If an end of a
communication from the desktop is not received for a predefined or threshold period
of time, the PCF and/or RAN determine that the desktop has lost the link and generate
the notification to the other users as described above. Additionally and/or
alternatively, the PCF and/or RAN can further monitor RTP/ User Datagram Protocol
(UDP) packets received from the desktop. If RTP/UDP packets are not received from
the desktop for a threshold period of time, the.PCF/RAN determines that the desktop
is lost and generates the notification. The present embodiments for desktop
communication can be employed with cellular networks, local area networks, satellite
communication networks, combinations of these networks, and other such networks.
[0063] The loss of a wireless link 112 can be caused by numerous factors, such
as, the wireless device 122 losing powe'r (e.g., battery being disengages and/or going
dead), the link being released for cause (e.g., aborted call, selection of another

operating mode, termination due to fee, reconnecting to a cell not able to serve the
wireless device), and other such causes for release. In these instances, the present
embodiments generate similar notifications as described above to the other one or
more users communicating with a wireless device that is released or disconnected
from a link due to power loss and other abnormal link release. In some instances, the
wireless device detects that the abnormal link release is going to occur and notifies the
system allowing the system to generate the notification to the other user(s) currently
communicating with the wireless device being lost. The notification can be an audio
notification, a text notification, a command to trigger the communication device to
generate a notification (audible tone, flash a light), and other notification. In some
implementations the audio notification can be a voiced announcement, for example, a
voiced message stating "lost call," "dropped call," or other such announcements. The
notification can further distinguish between a link loss and a loss due to battery failure
or other causes. For example, a tone or low beep can be generated to indicate the lost
call is due to a battery failure, while a short audible announcement stating "lost call"
can identify a loss due to a lost communication link.
[0064] Some embodiments generate a notification to a server (e.g., server 150)
when a link loss is detected. The server utilizes the notification to determine one or
more other users participating in a communication with the lost device. The server
then can generate a notification of the loss and fan the notification to all interested
parties. Additionally and/or alternatively, upon receiving a notification of a dropped
user (e.g., notification from a PCF), the communication device (e.g., wireless device
124) can query the server to identify which party or parties were dropped and/or lost.
[0065] The present embodiments provide notifications to users communicating
through short message services (text and/or typed messages). Short messaging
services allow messages to be forwarded from a first user to a second user, and the
second user can type in and forward a follow-up reply. These text communications
can continue through an unlimited number of communications between the users. In
• some embodiments, the text messaging is communicated across one or more traffic
channels. In utilizing traffic channel based text messaging, the present embodiments

detect when one of the users loses the link. Upon the detection of the lost link, the
system interjects a notice (e.g., a tone) and/or a text message to the remaining user(s).
The text message or other notification can be generated by the PCF or other system
component as described above.
[0066] Further, the present embodiments advantageously improve the average
user's experience and/or increases network capacity. Users expect a certain level of
quality of service from the wireless network provided, which can be generally equated
to the user experience. If the service is poor, inconsistent and/or painful for the user
(e.g., high percentage of lost calls), the user's experience is lower, and his/or
frustration level with the system increases. Many systems attempt to achieve a
defined fixed sensitivity to achieve a desired user experience. For example, some
systems tolerate a fixed percentage (e.g., 1%, 2% or some other percentage) of lost
connections.
[0067] The present embodiments reduce a users' frustration level by quickly
notifying the user of the lost connection, avoiding long periods of uncertainty of
whether the other user is still on the line, and making link outages less painful. The
quick notification greatly improves users' experiences and increases users'
satisfaction.
[0068] Additionally, users are also likely to remain satisfied, at least at pervious
satisfaction levels, with an increased percentage of lost calls because the present
embodiment notifies the users of the lost connections. This allows the same system to
be operated at a higher capacity. Operating a higher capacity may result in an
increased number of lost connections and/or calls, but users are more tolerant to
losing connections because they are quickly notified. Therefore, the system can
increase capacity without decreasing user satisfaction.
[0069] For example, some systems can increase their tolerated fixed percentage
of lost connections by 1%, 3% or more while still at least maintaining the same user
experience. Some systems may carry, for example, 1.25 times more load when users
tolerate an increase in lost connections from 1% to 5%. In some embodiments,
simulations are employed to estimate the increased percentage of lost connections that

will be tolerated while providing the same user experience. These simulations
estimate an increased percentage of lost connections based on a percentage increase in
system capacity. For example, if a system capacity is increased by 10%, the
simulation may define the RF loss probability to be increased by about 2-3%.
Because the present embodiments provide notification, users may tolerate an increase
of 3% of lost connections. Therefore, in one sense of the word capacity, the
simulation defines the increased capacity of about 10%. The ratios between the RF
loss probability and increased capacity depends on the system, the components of the
system, the amount of interference in the area covered and other such factors. The
simulation, however, attempts to take these parameters into consideration and provide
accurate estimations of capacity loads.
[0070] The present embodiments improve user experience with the same system
capacity and/or an increase in system capacity. Additionally and/or alternative, the
present embodiments resulting in users tolerating increased numbers of lost
connections allowing the system to increase system capacity (e.g., system can carry
~1.25x more load, when users tolerate 5% lost connections instead of 1%).
[0071] The present embodiments can, in some embodiments, further release
network resources upon the detection of a lost communication link. The RAN and/or
PCF can forward the notification to the remote user, and further notify the MSC, the
server and/or other system controllers and components. The MSC and/or server can
initiate the release of network resources. Due to the notification to the MSC and/or
other components of the system, the resources can, in some implementations, be freed
up sooner than would have otherwise been freed up. The freed up system resources
can then be utilized with other communications. Further, previous systems typically
continued to upload a users data (e.g., audio) for the user that were not dropped. This
uploaded data is typically just dumped, particularly when the data is not buffered
(e.g., instantaneously transmitted).
[0072] Some present embodiments alternatively buffer or store communicated
data (whether voice or data). The amount of data stored can be defined by any
number of parameters, but not limited to, a period of time, when a user stops talking,

until a confirmation or receipt is received from a second user, and other such
parameters. In the event a first user is speaking and the other user of the
corrmiunication is lost, the first user may continue to speak until and/or after the
notification is received. The buffering can similarly save some or all of this
communication data. In some embodiments, the system can forward this stored data
to the second user at a later time, and/or over a different radio frequency technology
or other communication medium (e.g., voice mail, send as email with audio
attachment; or through alternative means).
[0073] Still further, when a first user who is speaking loses the connection, the
buffered data can be saved. This saved data can be later retrieved by the lost user,
and/or other users, so that the user(s) can identify when during a conversation a loss
occurred and what information was and was not communicated.
[0074] The present embodiments provide notification for lost connections for
other types of communication besides batch or data communications. For example,
some embodiments additionally and/or alternatively provide notification of a lost
party during wireless interconnect or standard two-way voice corhmunications. Some
voice interconnect paths allow data to also be communicated, but primarily, voice
paths provide voice communications between two or more users, such as cellular
communications and the like.
[0075] As described above, some wireless devices can detect their own loss of a
connection. These wireless devices can then notify the local user of the loss. For
example, a first wireless device can wirelessly communicate with a second wireless
communication device. If the first wireless device detects a loss of the
communication link (e.g., RF link) with the base station, the first wireless device can
generate a beep indicating to the local owner of the first wireless device that the
wireless link was lost. The first wireless devices and the wireless communication
system are, however, incapable of notifying or initiating a notification to the second
wireless device participating in the communication.
[0076] The second user is unaware of the loss. As such, the second user typically
continues with the conversation and/or waits for further comments from the first user.

Because the second user does not know why the first user is not speaking, the second
user may wait extended amounts of time before deciding that the first user is no
longer on the connection. Further, the second user does not know why the first user is
disconnected. This waiting can be a significant waste of time, and is particularly
frustrating. Further, the resources to maintain the connection of the second user is
wasted valuable resources that could be utilized with other users. The ambiguity of a
lost connection can be particularly evident when the user of the wireless device that is
lost is using a speaker phone.
[0077] The present embodiments detect the link loss with a first wireless
communication device and provide notification to one or more other communication
devices that the first wireless device lost the wireless link. This notification
significantly reduces and/or avoids the other user(s) wasting time waiting for the first
user. Further, some embodiment release communication system resources once the
notification has been forward to the other user(s), freeing up the resources for other
communications. Additionally, one or more of the other communication devices can
be shut down and/or instructed to enter into a semi-dormant or RSCI state to
conserver power.
[0078] FIG. 6 depicts a simplified block diagram of a communication system or
network 610 providing voice communication over a voice path. A first wireless
device 622 wirelessly communications over a wireless link 612 with a first base
station or BTS 630 of a first RAN 634. The first RAN further couples with a first
MSC 636.
[0079] The first MSC 636 established communication channels, typically over a
PSTN 652, with one or more wireless devices 672 and/or other wired devices 626.
For example, the first MSC can couple with a second MSC 660 through the PSTN
652. The second MSC 660 couples with a second RAN 662 that includes a second
BTS 664. The BTS 664 wireless communicates over a second wireless link 670 with
a second wireless device 672.
[0080] FIG. 7 depicts a simplified graphical representation of time-line logic
flow 710 of the signaling between components of the communication system

according to voice communication systems without the implementation of the present
embodiments. Initially at step 720 a wireless communication link is lost and/or
dropped between a first wireless device 622, such as a first MS, and a transmitter,
such as a BTS 630. The local RAN 634 or local the MSC 636 associated with the
communication link 612 to the first MS 622 detects the loss at step 722. The MSC
instructs, at step 724, the release of the communication path and/or channel to the .
second communication device 672, such as a second MS. The second MS is not
notified and is unaware of the loss of connection with the first MS for an extended
period of time 740. This is wasted time for the second user.
[0081] FIG. 8 depicts a simplified graphical representation of time-line logic
flow 810 of the signaling between components of the communication system, such as
system 610 providing voice communication paths, that implements notification of lost
wireless links according to the present embodiments. At step 820, a wireless
communication link is lost and/or dropped between a first MS 622 and a BTS 63.0.
The local RAN 634 or local MSC 636 associated with the communication link 612 to
the first MS 622 detects the loss at step 822. The MSC or RAN generates and injects
a notification to the second MS 672 of the lost link at step 824. At step 826 the
second user receives the notification. The notification can be a tone or other audio
notification forwarded to the second MS, a command to cause the second MS to
generate a tone, or other such notification. Following the injection of the notification,
the MSC issues commands at step 830 to release of the communication path and/or
channel to the second MS. Because of the early notification, a significant amount of
the second user's time 840 is saved. For example, without the notification the user is
unaware of the lost connection and may stay on and/or continue talking on the line for
5-10 or more seconds. Alternatively, some embodiments generate the notification to
the remaining one or more users of the loss in less than a second. This saves the users
significant amounts of time and frustration.
[0082] In the present embodiments, typically the RAN 634 and/or a PCF detect
the loss of the wireless link with the wireless communication device (e.g.,
communication device 622). The RAN notifies the MSC 636 of the lost link. In

some embodiments, the RAN generates and injects the notification to the second
communication device (e.g., communication device 672). The MSC releases the
communication channel with the second communication device after the RAN has
forwarded the notification. In some implementations, the RAN notifies the MSC of
the lost link after the RAN has forwarded the notification. As an example, the MSC
can typically implement a trunk release in about 1,5 seconds. The notification can
typically be generated and forwarded (by the RAN or MSC) in about 0.2 seconds. As
such, the notification is received at the second device about 1.3 second before the
communication trunk is released. Therefore, the present embodiments can save users
at least about 1.3 seconds in instances when a user might notice the release of the
communication channel, and typically can save users significantly longer amounts of
time (e.g., in excess of 5 seconds in some instances) because users typically are
unable to detect the channel has been released and they may continue to talk to the
dead line.
[0083] FIG. 9 depicts a simplified graphical representation of communication
logic flow 910 between components of the system 610 when providing voice
communications over voice communication paths where the serving or local PCF
provides the notification of the lost user. In the process 910, the first MSC 636
generates and forwards the notification of the lost connection. At step 920, a first
local RAN 634 detects a loss of the wireless link 612 between a BTS and a first MS
622. In step 922, the first local RAN issues a release command to the first MS. In
step 924, the first RAN issues a clear request to the first local MSC 636. In step 926,
the first MSC returns a clear command.
[0084] In step 930, the first local MSC 636 generates and injects a notification to
a second remote MS 672 that the first MS was lost. At this point the second user
knows that the first user is lost and does not have to wait any longer to deteraiine if
the first user is present or not.
[0085] The first MSC further issues an Integrated Services Digital Network
(ISDN) user part protocol (ISUP) request in step 932 to release the communication
channel to the PSTN 652. In step 934, the PSTN forwards the ISUP release request to

the second remote MSC 660. The second MSC generates a clear command and
forwards the clear command in step 936 to the second remote RAN 662. In step 940,
the second RAN forwards a release order to the second MS 672 to release the wireless
link 670. In step 942, the second MS returns a confirmation of the release order. In
step 944, the second RAN forwards a clear complete notification to the second MSC.
[0086] In some embodiments, the process 910 can include additional, optional
step 950 that occurs prior to step 942 and the confirmation of the release order. In
step 950, the second MS forwards a communication to one or more servers (e.g.,
server 650) notifying the server that the first MS has lost connection. This allows the
servers to release resources, and record transaction statistics (e.g., stop billing for
communication time). When communicating over a voice path, it is often difficult for
the RAN and/or MSC to notify the server of the lost link. However, the end points
(i.e., the MSs) are generally aware or become aware of the lost connection. These end
points are in the same communication group, they are exchanging communications
with each other. As are result, the second MS can initiate the notification to the server
without excess over head.
[0087] The optional step 950 may be beneficial in-many situations. For example,
when a group call is taking place, and the speaking user loses the voice path (RF loss),
the server does not know the speaking user is gone. In step 940, one or more of the
other communication devices (e.g., 672 and/or 626) participating in the conference
call are notified that the speaking user has been lost from the voice path. Step 950
allows the one or more other communication devices to notify the server, allowing the
server to release resources and/or open the control to the other users.
[0088] In some alternative embodiments, the local RAN 634 generates the
notification to the one or more other parties participating in a communication with a
first wireless device that loses the wireless link. FIG. 10 depicts a simplified
graphical representation of communication logic flow 1010 between components of
the system 610 when providing voice communications over voice communication
paths where the serving or local RAN provides the notification of the lost user. In
step 1020, the first local RAN detects the loss of the wireless link 612 with first MS

622. In step 1022, the first RAN issues a release order to the first MS. In step 1024,
the first local RAN 634 generates a notification and forwards the notification to the
second remote MS 672. At this point the second user is aware of the loss of the first
MS and does not continue listening to dead air.
[0089] In step 1026, the first RAN issues a clear request to the first local MSC
636. In step 1030, the first MSC returns a clear command. In step 1032, the first
local MSC 636 generates an ISUP request to release the communication channel to
the PSTN 650. The PSTN forwards the ISUP release request in step 1034 to the
second remote MSC 660. In step 1036, the second MSC forwards a clear command
to the second remote RAN 662. In step 1040, the second RAN issues a release
command to the second MS 672 to release the wireless link 670. In step 1042, the
second MS returns a confirmation of the release order. In step 1044, the second RAN
forwards a clear complete notification to the second MSC.
[0090] The embodiment of process 1010 avoids the delays associated with the
generation of the clear request and clear commands between the first RAN and first
MSC, steps 1026 and 1030, respectively. Therefore, in some implementations, the
process 1010 can be implemented to further reduce the amount of time the second
user might listen to the lost link.
[0091] The present embodiments advantageously improve the average user's
experience and/or allows for increased network capacity. The notification to the users
of lost connections reduces users' frustration levels, and improves user experience.
Further, because of the reduced frustration levels, users are more likely to tolerate
increased numbers of lost connections. As a result, some systems according to the
present embodiments increase the system capacity while still maintaining user
satisfaction levels. For example, in some implementations systems can carry ~1. lx
more load when users tolerate about -1% more lost connections (e.g., from 2% to 3%
lost connections).
[0092] Additionally, because the system detects the lost connection, some
embodiments terminate the use of system resources in reduce time. The releasing of

system resources frees up these resources for other connections, allowing for an
increase in system capacity.
[0093] FIG. 11 depicts a simplified flow diagram of a process 1110 for use in
determining whether a system or network is implementing the present embodiments
to detect wireless link loss and to notify one or more other users of the loss. In step
1120, a communication is initiated between a first wireless device and at least a
second device (wireless or wired). The communication can be dispatch
communication (e.g., PPT, voice-over-IP and other such dispatch communications) or
a voice communication (e.g., cellular voice call). In step 1122, the process causes the
wireless communication link with the first device to be lost. For example, the signal
path can be obstructed, the wireless device can be moved into an RF loss, power to
the wireless device can be disconnected (battery loss), and/or other such induced
connection losses.
[0094] In step 1124, the commands and/or communications to the second
communication device are monitored. In step 1126, it is determined if the second
device receives a notification of loss. If the notification is not detected the process
terminates. In some implementations, if the notification is not detected the process
optionally proceeds to step 1132. If the notification is detected, step 1130 is entered
where the process identifies the system as employing the present embodiments.
[0095] In some embodiments, optional step 1132 is included, where it is
determined if the system generates a connection release order for the second
communication device. If the release order is not received, the process terminates. If
a release order is received, the process identifies the system as employing the present
embodiments. In some embodiments, the detection of the connection release order is
to be received within a predefined period for the process to indicate the system is
employing the present embodiment.
[0096] In some embodiments, the process 1110 can further initiate a second
communication between the first and second devices. The communication can then,
be terminated through normal termination from the first device (e.g., first device
performs a normal hang-up). The process can then monitor the second

communication device to determine if the termination is different and/or if the second
device receives a notification.
[0097] In some present embodiments, a notification can additionally be
forwarded to one or more users when another user loses a connection or purposely
disconnects (e.g., hangs up). The notification when a user purposely disconnects can
be a different notification than the notification forwarded when a lost connection is
detected. For example, the notification of an intentional disconnect can be a different
tone, a different voice message, different text message display, and/or other such
notifications or combinations of notifications.
[0098] The increased capacity further allows system and/or communication
service providers with potential increased revenue. Increasing the system capacity
may result in increased lost connections. The potential lost billable minutes due to the
early notification and release of resources provided by the present embodiments is
minimal compared with the gains achieved through increased system capacity and/or
user satisfaction that potentially results in increased customers. For example, if a
system capacity providing batch communication (e.g., PTT communications) is
increased by 25%, the increase in lost or dropped connections may be about 2%. The
average length of time for a PTT transmission is about ~5 seconds. As discussed
above, the notification to the party not lost reduces user time on the system by about 3
seconds, resulting in a 3 second loss of billing time per lost connection. This 3 second
lost billing equates to only about a 1% loss of revenue ((2%* ~3)/5 =~1%).
Alternatively, the present embodiments allow for, in some implementations, a 25%
increase in system capacity. Thus, the 25% increase in system capacity is much
greater than the loss of about 1% billable minutes.
[0099] While the invention herein disclosed has been described by means of
specific embodiments and applications thereof, numerous modifications and
variations could be made thereto by those skilled in the art without departing from the
scope of the invention set forth in the claims.

WE CLAIM :
1. A method for notifying a user of a loss of a wireless connection, comprising:
establishing a communication connection between a first communication device
and a second communication device over a communication network, where the first
communication device wirelessly communicates with the second communication
device over at least a first wireless link;
detecting a loss of the first wireless link with the first communication device
through a packet control function (PCF); and
notifying the second communication device of the loss of the connection with the
first communication device wherein the notifying comprises generating a notification
from the PCF, and injecting the notification onto the communication connection
directed to the second communication device.
2. The method as claimed in claim 1, wherein detecting a loss of the first wireless
link comprises:
determining whether the lost wireless link was purposely disconnected; and
wherein notifying the second communication device comprises preventing the
notifying the second communication device when the lost wireless link was purposely
disconnected.
3. The method as claimed in claim 1, comprising:
the PCF notifying a server of the detected loss of the wireless link with the first
communication device; and
receiving, from the server, an identification of the second communication device
for accurately forwarding the notification by the PCF to the second communication
device.
4. A system for use in providing wireless communication comprising:
a base station that wirelessly communicates with a first communication device
over a wireless link;
a packet control function (PCF) coupled with the base station;

a second communication device communicationally coupled with the first
communication device through at least the PCF;
wherein the PCF detects a loss of the wireless link and generates a notification
and forwards the notification to the second communication device notifying the second
communication device that the wireless link has been lost.
5. The system as claimed in claim 4, comprising:
a packet data serving node (PDSN) coupled with the PCF and further coupled
with a distributed network, for the second communication device to be
communicationally coupled with the first communication device through at least the
PCF, PDSN and the distributed network.
6. The system as claimed in claim 4, comprising:
a server communicationally coupled with the PCF for the PCF to query the
server to identify the second communication device prior to forwarding the
notification.



ABSTRACT


METHOD AND SYSTEM FOR USE IN REDUCING COST
ASSOCIATED WITH LOST CONNECTIONS IN
WIRELESS COMMUNICATION
The present embodiments provides for notifying a remote communication
device (124/126) when a local wireless device (122) loses its wireless link (112). A
method detects when a wireless connection (112) is lost with a first communication
device (122) identifies a second communication device (124, 126) that is
communicating with the first device, and notifies the second device of the lost link.
The notification of the lost link is supplied while the method provides batch
communications. Voice communications, where a remote device is notified when a
local device loses its wireless connection, can be provided. The second device can be
determined by querying a server (150). The notifying can include forwarding an in-
band tone, and/or generating a real time protocol packet. The loss of the link is
detected through a radio access network (134), a packet control function (132), and/or
a mobile switching center (136).

Documents:

0055-kolnp-2007 abstract.pdf

0055-kolnp-2007 assignment.pdf

0055-kolnp-2007 claims.pdf

0055-kolnp-2007 correspondence others.pdf

0055-kolnp-2007 correspondence-1.1.pdf

0055-kolnp-2007 description (complete).pdf

0055-kolnp-2007 drawings.pdf

0055-kolnp-2007 form-1.pdf

0055-kolnp-2007 form-3.pdf

0055-kolnp-2007 form-5.pdf

0055-kolnp-2007 international publication.pdf

0055-kolnp-2007 international serch authority report.pdf

0055-kolnp-2007 p.a.pdf

0055-kolnp-2007 pct form.pdf

0055-kolnp-2007 priority document.pdf

55-KOLNP-2007-(04-02-2013)-ABSTRACT.pdf

55-KOLNP-2007-(04-02-2013)-ANNEXURE TO FORM 3.pdf

55-KOLNP-2007-(04-02-2013)-CLAIMS.tif

55-KOLNP-2007-(04-02-2013)-CORRESPONDENCE.pdf

55-KOLNP-2007-(04-02-2013)-DESCRIPTION(COMPLETE).pdf

55-KOLNP-2007-(04-02-2013)-DRAWING.pdf

55-KOLNP-2007-(04-02-2013)-FORM 2.pdf

55-KOLNP-2007-(04-02-2013)-PA.pdf

55-KOLNP-2007-(04-02-2013)-PETITION UNDER RULE 137.pdf

55-KOLNP-2007-(09-11-2012)-CORRESPONDENCE.pdf

55-KOLNP-2007-(09-11-2012)-OTHERS.pdf

55-KOLNP-2007-(20-02-2013)-CORRESPONDENCE.pdf

55-KOLNP-2007-(20-02-2013)-FORM 3.pdf

55-KOLNP-2007-ASSIGNMENT-(12-12-2011).pdf

55-KOLNP-2007-ASSIGNMENT.pdf

55-KOLNP-2007-CANCELLED PAGES.pdf

55-KOLNP-2007-CORRESPONDENCE-(12-12-2011).pdf

55-KOLNP-2007-CORRESPONDENCE.pdf

55-KOLNP-2007-EXAMINATION REPORT.pdf

55-KOLNP-2007-FORM 18-1.1.pdf

55-kolnp-2007-form 18.pdf

55-KOLNP-2007-FORM 6.pdf

55-KOLNP-2007-FORM-1-(12-12-2011).pdf

55-KOLNP-2007-FORM-2-(12-12-2011).pdf

55-KOLNP-2007-FORM-3-(12-12-2011).pdf

55-KOLNP-2007-FORM-5-(12-12-2011).pdf

55-KOLNP-2007-FORM-6-(12-12-2011).pdf

55-KOLNP-2007-GPA.pdf

55-KOLNP-2007-GRANTED-ABSTRACT.pdf

55-KOLNP-2007-GRANTED-CLAIMS.pdf

55-KOLNP-2007-GRANTED-DESCRIPTION (COMPLETE).pdf

55-KOLNP-2007-GRANTED-DRAWINGS.pdf

55-KOLNP-2007-GRANTED-FORM 1.pdf

55-KOLNP-2007-GRANTED-FORM 2.pdf

55-KOLNP-2007-GRANTED-FORM 3.pdf

55-KOLNP-2007-GRANTED-FORM 5.pdf

55-KOLNP-2007-GRANTED-SPECIFICATION-COMPLETE.pdf

55-KOLNP-2007-INTERNATIONAL PUBLICATION.pdf

55-KOLNP-2007-INTERNATIONAL SEARCH REPORT & OTHERS.pdf

55-KOLNP-2007-OTHERS.pdf

55-KOLNP-2007-PA-CERTIFIED COPIES-(12-12-2011).pdf

55-KOLNP-2007-PA.pdf

55-KOLNP-2007-PETITION UNDER RULE 137.pdf

55-KOLNP-2007-REPLY TO EXAMINATION REPORT.pdf

abstract-00055-kolnp-2007.jpg


Patent Number 260835
Indian Patent Application Number 55/KOLNP/2007
PG Journal Number 22/2014
Publication Date 30-May-2014
Grant Date 23-May-2014
Date of Filing 04-Jan-2007
Name of Patentee MOTOROLA MOBILITY, INC
Applicant Address 600 NORTH US HIGHWAY 45,LIBERTYVILLE,IL 60048,UNITED STATES OF AMERICA
Inventors:
# Inventor's Name Inventor's Address
1 HARRIS JOHN M 2232 N. KENMORE AVENUE, #1, CHICAGO, IL 60614
2 HART THOMAS B 936 PEMBER CIRCLE, WEST DUNDEE, IL 60118
3 CROCKER RONALD T 3N800 MEDOWRIDGE CIRCLE, ST.CHARLES, IL 60175
PCT International Classification Number H04M3/00
PCT International Application Number PCT/US2005/025278
PCT International Filing date 2005-07-18
PCT Conventions:
# PCT Application Number Date of Convention Priority Country
1 10/902,363 2004-07-29 U.S.A.