Note: Descriptions are shown in the official language in which they were submitted.
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COMPUTER NETWORK TELEPHONY ADAPTER DEVICE
BACKGROUND OF T~:E INVENTION
1. Field of the Invention
The present invention relates generally to a computer network
telephony adapter that facilitates the use of a conventional
telephone for both traditional telephony and computer network
telephony. More particularly, the invention relates to an
adapter device that can be simultaneously connected to the
public telephone network, a conventional telephone, and a
computer, which allows the conventional telephone to be used
for both traditional telephony and computer network telephony.
The invention also relates to a communication system that
facilitates the use of a conventional telephone for both
traditional and computer network telephony. The invention
further relates to a method of controlling telephonic voice
communications via the public telephone network and a computer
network.
2. Description of Related Art
Computer network telephony allows voice communication over a
computer network, such as the Internet or an Intranet.
Computer network telephony is becoming increasingly important
in the so-called "information age," in both the private sector
and the business world. This is because of the ease with
which the world-wide compute. network (the Internet) can be
accessed and used.
Most private sector users, and many businesses, access the
Internet using a modem-equipped computer to dial up an
Internet service provider (ISP) using a local telephone
number. The ISP then establishes communication between the
Internet and the computer. Because the ISP's telephone number
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is usually a local call, world-wide communication- via the
Internet can be achieved a~ the cost of a local telephone
call. Alternatively, many business and government agencies
have dedicated Internet connections, thus not requiring
Internet access via an ISP.
The development of the Internet, with its concomitantly low
communication costs, has spawned its use for voice
communications, conventionally known as "Voice over Internet
Protocol" (VoIP). This technology is currently utilized in
three distinct platforms: (1) the conventional computer-to-
computer platform, (2) the telephone Gateway platform, and (3)
the Intranet platform. The first two platforms allow a caller
to talk to another party anywhere in the world for the price
of a local call. The third platform allows businesses to use
an Intranet for voice communication, primarily via central
gateways and routers, between remotely located branch offices.
The conventional computer-to-computer platform requires
coordination between the com:-nunicating parties. Each party
must first access the Internet. During the Interr_et telephone
call, the caller's voice is digitized by the computer's sound
card and sent out over the Internet as compressed and
packetized TCP/IP traffic. At the receiving end, this data is
received and processed by software to extract and decompress
the voice signal, and is the., sent to the receiving computer's
speaker(s). However, this platform will not work with a
conventional telephone. It requires a computer that is
equipped with a sound card, microphone, and one or more
speakers.
Private companies have entered the Internet telephony market
by developing the telephone Gateway platform. These companies
utilize proprietary Gateways connected to the public telephone
network and the Internet. ~o initiate an Internet telephone
call, a user dials into a local Gateway via the public
telephone network. The local Gateway will then contact a
remote Gateway, via the Internet, within the local telephone
region of the party being ca_led. The remote Gateway then
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dials the number of the person being called, allowing the two
parties to communicate over the Internet. Because both calls
are local, the entire call takes place without long-distance
charges. However, most Gateway solutions are proprietary and
will not work with other vendor Gateways, and are not a
practical solution because of expense and complication.
The Intranet platform allows businesses with remotely located
branch offices to communicate using VoIP technology. This is
accomplished much like the computer-to-computer platform,
except the business's Intranet is used instead of the
Internet. This platform, too, will not work with a
conventional telephone and requires computers that are
equipped with a sound card, microphone, and one or more
speakers. However, the sound card, speakers, and microphone
setup has lesser sound quality than a conventional telephone
because, among other reasons, unlike a conventional telephone
it lacks echo cancellation. Where speakers are used, it also
lacks the privacy afforded by a conventional telephone.
2G
Because of the low cost, it is reasonably foreseeable that the
telephony infrastructure of the future will be based on VoIP.
Thus, there is a need to bridge the gap between the existing
public telephone network and the future infrastructure. The
major problem with existing platforms is that they will not
work with a conventional telephone, or they require use of a
proprietary Gateway server. There are telephones and
interface devices that connect to a computer or to a Local
Area Network (LAN); however, these devices do not permit
continued use of the public telephone network.
Another device, disclosed in U.S. Patent No. 5,838,665, links
the public telephone network ar_d the Internet via an adaptor
telephone device. This device, however, requires the user to
replace his or her existing telephone with the adapter device.
Additionally, this device connects to the computer's sound
card, thus monopolizing its functionality and preventing its
use for other applications when utilizing this device.
30-OI-2UU1 _ -
~~'UUU;iti6,
3a
WO 98/37665 to Fonefriend relates to an Internet switch box. A
relay means is provided for (i) either connecting a first
telephone set to a primary network or (ii) connecting said
first telephone set to a secondary network. According to a
first mode of operation, in case a user intends to establish a
connection via the secondary network, e.g., the Internet, the
user will first dial the PSTN telephone number of the intended
call recipient. Once the called telephone is answered, both
parties initiate via a simple key stroke the switch to the
secondary network. The PSTN call is then disconnected and the
call via the Internet is initiated. In other words, first a
"regular" call is necessary and both parties have the to ,use a
key at their switch boxes for switching to the Internet. Thus,
the switch is to be done during the call and by both parties .
According to a second mode of operation, PSTN charges can be
avoided via prearrangement.
AMENDED SHEET
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Thus, there is a need for a device that allows users to take
advantage of the current Internet and Intranet telephony
infrastructure, without sacrificing the service level,
stability, and connectivity of the current public telephony
infrastructure, or having to replace their existing telephone
with a specially designed device. There is also a need for a
device that bridges these two infrastructures without
requiring a separate, proprietary Gateway solution.
SUMMARY OF THE PRESENT INVENTION
It is therefore a principal object of the present invention to
provide a telephone adapter that is simultaneously connected
to a public telephone network, a conventional telephone, and a
computer to allow computer network telephone calls to be
conducted using the conventional telephone.
Another object of the present invention is to provide an
adapter that is connected simultaneously to a public telephone
network, a conventional telephone, and a computer to allow
computer network telephone calls to be conducted using the
conventional telephone, without sacrificing the sound quality
and privacy afforded by a conventional telephone.
Yet another object of the present invention is to provide an
adapter that is connected simultaneously to a public telephone
communication line, a conventional telephone, and a computer
to allow computer network telephone calls to be conducted
using the conventional telephone, such that the adapter is
controlled and powered by the computer.
In one aspect of the present invention, a telephone adapter
includes first, second, and third receiving means. The first
receiving means receives analog telephony signals from a
public telephone r_etwork. The second receiving means receives
analog telephony signals from a telephone. The third
receiving means receives control signals and electrical power
from the computer. A first activatable and deactivatable path
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means transmits analog telephony signals between t'_le first and
second receiving means. A second activatable and
deactivatable path means converts analog telephony signals
received from the second receiving means to digitized signals
and transmits the digitized signals to the computer. The
second path means also converts digitized signals received
from the computer to analog telephony signals and transmits
the analog telephony signals to the second receiving means.
Controller means, responsive to the control signals,
deactivates the first path means and activates the second path
means while the first path means is deactivated.
In a further aspect of the present invention a communication
system includes a telephone, a computer connected to a
computer network, and an adapter device connected to the
telephone, a public telephone network, and the computer. The
adapter device includes first, second, and third receiving
means. The first receiving means receives analog telephony
signals from a public telephone network. The second receiving
means receives analog telephony signals from a telephone. The
third receiving means receives control signals and electrical
power from the computer. A first activatable and
deactivatable path means transmits analog telephony signals
between the first and second receiving means. A second
activatable and deactivatable path means converts analog
telephony signals received from the second receiving means to
digitized signals and transmits the digitized signals to the
computer. The second path means also converts digitized
signals received from the computer to analog telephony signals
and transmits the analog telephony signals to the second
receiving means. Controller means, responsive to the control
signals, deactivates the first path means and activates the
second path means while the first path means is deactivated.
In yet a further aspect of the present irwention a method of
controlling telephonic voice communications includes
connecting an adapter device between a public telephone
network and a telephone, and connecting the adapter to a
computer. The computer transmits electrical power and control
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signals to the adapter for establishing at least first and
second operating modes. In the first operating mode, analog
telephony signals are transmitted between the telephone and
the public telephone network via the adapter device. In the
second operating mode, analog telephony signals are converted
to digitized signals in the adapter and transmitted to the
computer, and digital signals received from the computer are
converted to analog telephony signals in the adapter and
transmitted to the telephone.
In still a further aspect of the present invention, an adapter
device for interconnecting a telephone with a public telephone
network and a computer network includes a first connector, a
second connector, a third connector, signal processing
circuitry electrically connected to the third connector, and a
switch electrically connected by separate switch contacts to
the first and second connectors, and the signal processing
circuitry. The switch electrically connects the first
connector to the second connector in a first position, and
electrically connects the second connector to the signal
processing circuitry in a second position.
These and other objects, aspects, advantages and features of
the present invention will become more apparent to those
skilled in the art when the following detailed description is
- read in conjunction with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
In the following detailed description, reference will be made
to the attached drawings in which:
Figure 1 illustrates the overall telephony communication
system and the integration of the computer network telephony
adapter with the system, in a first embodiment of the present
invention.
Figure 2 is a schematic diagram of the internal circuitry of
the computer network telephony- adapter of the present
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invention.
Figure 3 illustrates the an overview of the overall system
software interaction between the adapter and computer,
according to the present invention.
Figure 4 is a flowchart illustrating the operation of the
present invention for a public network telephone call.
Figure 5 is a flowchart illustrating the operation of the
present invention for an incoming computer network telephone
call.
Figure 6 is a flowchart illustrating the operation of the
present invention for an outgoing computer network telephone
call
Figure 7 illustrates the overall telephony communication
system and the integration of the computer network telephony
adapter with the system, in a second embodiment of the present
inventior~ .
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Figure 1 depicts the overall telephony communication system 10
and the integration of adapter 30 into the system 10. The
overall system includes the public telephone network 14, a
host computer 16 connectable to a computer network 18, and a
conventional telephone 12. Computer 16 includes a
microprocessor (not shown) and memory (not shown) which stores
software. Adapter 30 is integrated into the system 10 by
connecting it to the public telephone network 14, the computer
16, and the conventional telephone 12.
Adapter 30 is connected to the public telephone network 14 via
a conventional telephone wall jack 22. This can be
accomplished by connecting conventional telephone wiring 24
between the wall jack 22 and adapter 30, which is also
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equipped with telephone connectors and which will be discussed
further. Conventional telephone wiring 24 also interconnects
the telephone 12 and adapter 30.
Adapter 30 and computer 16 are preferably interconnected via
one of the computer's universal serial bus (USB) ports 25.
This can be accomplished by inserting a cable 28 between
adapter 30 and the computer's USB port 25. One or more USB
ports is standard in new computer systems, and can be added to
an existing system quite readily by an ordinarily skilled
artisan. The USB port 25 not only allows data communication
between adapter 30 and computer 16, but also provides power to
most of the adapter's internal circuitry. If, however, a user
desires adapter 30 to generate a unique ring signal for an
incoming computer network telephone call, an optional,
detachable power connection 26 can be provided. This is
because more power is required to generate a signal to ring
telephone 12 than a standard USB 25 can provide. Thus, if this
functionality is desired, adapter 30 is connected to a
conventional electrical power wall plug using the optional,
detachable power connector 26.
Computer 16 is connected to computer network 18, via
connection 23, using any method known to the ordinarily
skilled artisan. For example, connection 23 could be a
digital network communication cable, such as Category-5 cable,
or a wireless connection, such as an antenna. Alternatively,
connection 23 could be a dedicated digital communication line
whereby computer 16 is connected directly to the Internet.
Or, connection 23 could be standard telephone communication
wire connected between a modem (not shown) that is connected
to computer 16, and computer network 18. These examples are,
of course, not limiting and any connection known to an
ordinarily skilled artisan could be used to interconnect
computer 16 and computer network 18.
In a first embodiment, computer 16 is connected, via a
dedicated connection 23, to computer network 18. Computer
network 18 may be either ar: Intranet or the Internet, or both,
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depending upon the configuration of computer 16 and its
external peripherals. For example, the computer 16 could be
connected simultaneously to an Intranet and the Internet using
common communication wiring connected to a common server, as
is known in the art. Alternatively, computer 16 could be
connected to an Intranet and the Internet using separate
connections for each. Again, these examples are not limiting
and any configuratior_ known to the skilled artisan could be
utilized.
A detailed description of overall system 10 operation will be
further discussed below. However, referring now to Figure 2,
a detailed description of adapter 30 will be provided.
Adapter 30 is connected to public telephone network 14 via
connector 34, to telephone 12 via connector 36, and to
computer 16 via connector 72. Connector 82 allows optional
power connector 26 (discussed above) to be attached to adapter
30. These connectors will be discussed in further detail
below.
Adapter 30 includes circuitry 32 that provides the interface
to the telephone 12, the public telephone network 14, and the
adapter's internal circuitry. This circuitry 32 includes
connectors 34, 36, circuit connections 38, 42, and a switching
device 44. The connectors 34, 36 may be any device known to a
skilled artisan for receiving analog telephony signals, but in
the preferred embodiment are standard RJ11 telephone jacks.
The switching device 44 may be any type known to the
ordinarily skilled artisan. Examples include, but are not
limited to, an analog switch, or a software switch. In the
preferred embodiment, however, switching device 44 is a
double-pole, double-throw (DPDT) relay.
The normal, non-energized position of switching device 44 is
shown in Figure 2. This position interconnects connectors 34,
36 for public telephone network telephony communication.
Thus, if electrical power is not available to adapter 30,
conventional telephony functions can still be performed.
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Connected to circuit connection 42, via another switching
device 46, is a call hold terminator 48. Call hold terminator
48 allows an incoming public telephone network call to be
placed on hold. This is accomplished by moving switching
device 46 to interconnect the call hold terminator 48 and
circuit connection 42. As with switching device 44, switching
device 46 may be any type known to the ordinarily skilled
artisan, but in the preferred embodiment is a double-pole,
single-throw (DPST) relay. Additionally, call hold terminator
48 may be any loading device known to an ordinarily skilled
artisan, but in the preferred embodiment is a resistor.
Also connected to circuit connection 42 is ring detector
circuit 52. Ring detector circuit 52 senses an incoming
ringing signal received from the public telephone network 14
and sends a notification signal to microcontroller 54 (e.g., a
CPU or other software driven processor). Microcontroller 54
can then notify computer 16, via connector 72, that the public
telephone network line is ringing telephone 12. Thus, if a
computer network call is taking place when an incoming call is
received from the public telephone network 14, computer 16 can
notify the user with a distinct tone.
Connected to circuit connection 38 is off-hook detector
circuit 56. This circuit senses when telephone 12 receiver is
placed into either a calling mode or a call receiving mode by,
for example, taking the receiver of a conventional cradle-held
telephone off the hook, or pressing the "talk" button of a
cordless telephone, etc. This circuit also sends a
notification signal to computer 16 via microcontroller 54.
This allows computer 16 to send a notification signal to the
user's telephone receiver when a network telephone caller is
attempting to call the user over the computer network 18, and
the telephone is not hung up. This function will be discussed
in more detail when the overall operation is described.
A dual tone mufti-frequency (DTMF) detector circuit 58 can
also be connected to circuit connection 38. This circuit may
be incorporated into a single integrated circuit package with
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off-hook detector circuit 56, or may be realized separately
using an individual circuit. DTMF tone detector circuit 58
detects incoming DTMF tones from the public telephone network
14, which can be used to detect the telephone number of the
incoming caller. DTMF tone detector circuit 58 can also
detect the DTMF tones generated by telephone 12 when a user is
placing an outgoing call. The purpose of this latter function
will also be described in more detail below.
When the position of switching device 44 is set to allow
computer network telephony communication, circuit connection
38 is electrically disconnected from circuit connection 42 and
is electrically connected to interface circuit 62. This
circuit provides proper signal gains for transmitting and
receiving the telephony signals between computer 16 and
telephone 12. This circuit also provides proper impedance
matching between telephone 12 and the adapter's internal
circuitry, and provides 2-wire/4-wire conversion for the
signals passed to, and received from, the telephone 12. This
circuit can be any known integrated circuit package known to
the ordinarily skilled artisan, or can be realized using
discrete components. However, in the preferred embodiment
line interface circuit 62 is realized using a known interface
circuit having manufacturer's part number Ericsson PBL38710_1.
Connected to interface circuit 62 is audio processor 64.
Audio processor 64 converts the analog telephony signals
received from telephone 12 via interface circuit 62, into
serial signals. The serial signals are then transmitted to
microcontroller 54. Audio processor 64 also receives serial
digital signals from microcorltroller 54 and converts the
digital signals to analog telephony signals, which are then
transmitted, via interface circuit 62, to telephone 12. Audio
processor 64 may be controlled by microcontroller 54 to set
various audio processing parameters. Examples include, but
are not limited to, the audio processor 64 signal gain, and
side-tone (echo) gain back to telephone 12. Audio processor
64 may also include a tone generator to produce DTMF and call
progress tones which may be transmitted to telephone 12. This
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circuit can be any known integrated circuit package known to
the ordinarily skilled artisan, or can be realized using
discrete components. However, in the preferred embodiment
audio processor 64 is realized using known components,
comprising at least manufacturer's part numbers AMD AM79C203.
Microcontroller 54 controls the overall operation of adapter
device 30 using resident, o~-board software stored in memory
66, while functioning as a slave to computer 16. In other
words, software resident on computer 16 controls the operation
of microcontroller 54, whit~ in turn controls the operation of
adapter 30 using its own software. All telephone 12 status
information is transmitted from microcontroller 54 to computer
16, and microcontroller 54 is controlled based upon commands
received from computer 16, via connector 72. Microcontroller
54 includes ir_ternal memory 78, such as random-access-memory
(RAM), which can be used to store volatile information, for
example the user-specified ring cadence (discussed further
below). Microcontroller 54 ir_cludes parallel input-output
(I/O) ports that may be used to control switching devices 44
and 46, and ring generator 68 (discussed below), and to
monitor the status of ring detector circuit 52, off-hook
detector circuit 56, and DTMF tone detector circuit 58.
Microcontroller 54 also includes a bidirectional serial port
for transmitting and receiving digital data to and from audio
processor 64. Microcontroller 54 may be any software-driven
processor device known to an ordinarily skilled artisan, but
in a preferred embodiment is an Infineon C161U P-TQFP-100
generation controller.
Ring generator 68, connected between microcontroller 54 and
interface circuit 62, can provide an output signal for ringing
telephone 12, if, as noted previously, optional power
connector 26 is used. Ring generator 68 is controlled by
microcontroller 54 and can generate a signal which causes
telephone 12 to ring with a unique, user-specified cadence
when a network telephone call is received by the computer 16.
This signal can be, for example, a 20 Hz sine wave or square
wave output signal. The unique cadence can be set using
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software resident on computer 16, which is then stored in RAM
78 of microcontroller 54. If, however, optional power
connector 26 is not used, an external AC power plug is not
available, or the user simply does not desire to ring
telephone 12 when a network telephone call is received by
computer 16, then computer 1o can be configured to alert the
operator of an incoming net~Y~ork call. For example, the
computer's sound card could be used to generate a signal of
any desired fashion.
In alternative embodiments, special function circuits and
components discussed above (for example, one or more of ring
detector circuit 52, off-hook detector circuit 56, DTMF
detector circuit 58, and ring generator 68) may be replaced
with a digital signal processor (not shown) that performs
their functions.
Adapter 30 is physically co~~nected to computer 16 using USB
connector 72. While this connector may be any device known in
the art for interconnecting a processor and a USB port 25, in
a preferred embodiment this connector is a USB "Series B"
receptacle. As noted above, connector 72 can be connected to
a USB port 25 of computer 16 using a standard, detachable
cable 28 known to those of ordinary skill in the art.
Alternatively, cable 28 can be an integral part of adapter 30.
This integral cable would include a plug for connecting to a
USB port 25 of computer 16.
Connector 72 is electrically connected to microcontroller 54
via an interface controller 74. Interface controller 74
functions to match the electrical characteristics of adapter
30 with those of computer 16. Interface controller 74 also
interprets the serial data se~u.ences received from computer 16
as either control signals or processed computer network
telephony signals. Interface controller 74 may be a separate,
individual circuit component known to those of ordinary skill
in the art, but in a preferred embodiment is integrated into
the circuit package of microcontroller 54.
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The computer's USB port 25 is a 4-wire, polled, serial bus
that provides data transfer over two of the wires, and DC
electrical power over the other two wires. Therefore, as
previously noted, electrical power for adapter 30 can be
provided solely from the USB port 25 of computer 16, via USB
connector 72. This can be accomplished by transmitting the DC
power received from computer 16 to DC/DC converter circuitry
76. DC/DC converter circuitry 76 receives the DC power from
the computer and converts it ~.o the appropriate operating
voltage levels for the internal circuitry of adapter 30, and
for telephone 12 when disconnected from the public telephone
network 14. For clarity, the DC power connections are not
depicted in the Figures. However, the ordinarily skilled
artisan would readily understand that these connections exist.
As noted above, overall system operation is controlled by
software resident on computer 16. (However, in alternative
embodiments, the system operation may be controlled, in whole
or part, by a microprocessor located in the adapter (not
shown).) An overview of the software implementation is shown
in Figure 3. The software includes the microcontroller
software 84, the main program 86, configuration software 88,
and a network telephone client program 92. The
microcontroller software 84 configures adapter 30 to allow
both public telephone network telephony and computer network
telephony, and is downloaded to adapter 30 each time computer
16 is powered up. This software 84 allows microcontroller 54
to perform basic detection and signal transmission functions,
which have been discussed and which will be further discussed
in more detail below. If computer 16 is powered down, adapter
30 allows only public telephone network telephony. The
software on computer 16 also includes the main program 86.
Main program 86 controls the overall system operation and will
be discussed further below. Computer 16 further includes
software component 88, which is a configuration program for
gathering and implementing user-specified options. These
options include, but are not limited to, the network telephone
call ring cadence (discussed above), how a caller's telephone
number will be displayed (discussed below), and tile default
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configuration for outgoing network telephone calls (discussed
below). Computer 16 also includes in memory a network
telephone client program 92. Program 92 converts the
digitized telephony signals received from adapter 30 to
compressed and packetized TCP/IP data for transmission over
computer network 18. Program 92 also extracts and
decompresses the network telephony signals received from
network 18 as TCP/IP data. Program 92 can be any network
telephony software known to the ordinarily skilled artisan.
For example, this software could be Microsoft Netmeeting or
software available from Net2Phone. The software on computer
16 can be implemented using any operating system known to an
ordinarily skilled artisan, but in the preferred embodiment
the operating system is a graphical user interface.
Having described in detail the overall system 10, the internal
circuitry of adapter 30, and an overview of the software, a
detailed operational description of the system 10 and adapter
30 will now be provided. The following description covers the
three general operational configurations of the system when
computer 16 is powered up and controlling system operation,
these configurations cover: (1) an incoming public telephone
network call; (2) an incoming computer network telephone call;
and (3) an outgoing call over either network. Reference
should be made to Figures 1, 2 and 4-6, as necessary. In the
following discussions, the steps indicated in parentheses
correspond with applicable flowchart steps in Figures 4
through 6.
1. Incomina Public Telephone Network Call
When a user receives an incoming call (STEP 101) from the
public telephone network 14 while telephone 12 is not being
used, the telephone 12 is connected directly to the public
telephone network 14 as though adapter 30 were not present.
Ring detector 52 senses the incoming ringing signal (STEP
102), and DTMF detector circuit 58 determines the telephone
number of the calling party. The telephone number can then be
sent to computer 16, via microcontroller 54, and displayed on
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the user's computer 16 (STEP 103). Adapter 30 and computer 16
then sense if telephone 12 _s already being used for a network
call (STEP 104). If so, and the system is so configured,
adapter 30 will then alert computer 16 to issue a distinctive
tone to telephone 12. Specifically, if a network telephone
call is taking place when the user receives a public telephone
network call, the computer commands microcontroller 54 to
momentarily change the position of switching devices 44 and
46, and cause audio processor 64 to generate a distinct tone,
and then change switches 44, 46 back to their original
positions (STEPS 105-107).
The distinct tone generated by audio processor 64 will be
heard by the user, alerting the user of an incoming network
call. The user can then switch between the public telephone
network 14 and computer netc~~ork 18 callers in one of two ways.
First, the user could use hook flashes at telephone 12, which
would be sensed by off-hook detector circuit 56. This would
cause microcontroller 54 to change the position of switching
device 46 to connect/discorlr_ect connection circuitry 42
to/from call hold terminator 48 with each subsequent hook
flash (STEPS 108-118). Second, the user could use commands
directly from computer 16 to perform this same function. For
example, a software-driven graphical user interface (GUI)
could be utilized whereby a user could double-click on an icon
using a mouse, as is well-known in the art. Although the GUI
software embodiment is not -llustrated, its functionality can
be easily realized by an ordinarily skilled artisan.
When the call is complete, t=ne user simply hangs up telephone
12 in the normal manner. Off-hook detector circuit 56 senses
when the phone is hung up and sends a signal to
microcontroller 54, which sends a signal to computer 16. Both
microcontroller 54 and computer 16 are then reset to their
pre-call configurations.
2. Incoming Computer Network Call
If an incoming computer net:rork call is received (STEP 201),
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the network caller's number is identified and displayed on
computer 16 (STEP 202). Off-hook detection circuit 56 then
determines whether or not telephone 12 is hung up (STEP 203).
If telephone 12 is hung up, computer 16 alerts the user in one
of two ways (STEP 204). If the user is utilizing optional
power connection 82, then computer 16 will command
microcontroller 54 to cause ring generator 68 to generate a
unique, user-specified ring signal and transmit this to
telephone 12, via interface circuit 62 (STEP 205). However,
if optional power connection 82 is not used, or if the user
simply desires not to use this function and has configured
adapter 30 in this manner, then computer 16 will generate the
unique, user-specified signal and send the signal to the
computer's sound generation peripherals, such as a sound card
and speakers (STEP 206).
If off-hook detection circuit 56 determines that telephone 12
is not hung up, computer 16 will alert the network caller in
one of two ways (STEP 207). If computer 16 is so configured,
it will send a unique tone to telephone 12 to alert the user
of the incoming network call (STEP 208). The user can then
use hook flashes (or the GUI discussed above) to transfer
between the public network call and the computer network call
(STEPS 210-218). When a hook flash (or GUI operation) is used
to establish communication with the network caller, computer
16 will command adapter 30 to be reconfigured from its normal
position. Specifically, computer 16 will command
microcontroller 54 to change the position of switching device
44, thus connecting connection circuitry 38 to interface
circuit 62. Simultaneously, computer 16 will command
microcontroller 54 to configure audio processor 64 to begin
converting and transferring the telephony signals between
telephone 12 and computer 16 (STEP 212). A subsequent hook
flash will, of course, reconnect the public network caller to
telephone 12. If computer i6 is not configured to alert the
user, then computer 16 will send a busy signal to the network
caller (STEP 209).
While the user is being alerted to the computer network call
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(STEPS 205 or 206), adapter 30 is also monitoring the status
of telephone 12 using off-hook detector circuit 56 to
determine when the call is answered (STEP 219). When off-hook
detector circuit 56 senses that the call is answered, computer
16 either commands ring generator 68 to stop generating ring
signals or computer 16 stops generating alert signals,
depending upon the configuration, as discussed above (STEP
220). If, however, the network call is not answered within a
predetermined period of time (e. g., 30 seconds) the program
exits (STEP 221). Once the call is answered, computer 16
commands microcontroller 54 to reconfigure adapter 30, as
discussed above (STEP 212).
During the network telephone call, adapter 30 continues to
monitor public telephone network 14 for incoming calls (STEPS
221-224). Ring detector circuit 52 monitors connection
circuit 42 for a ring signal from the public telephone network
14 (STEP 222). If a ring signal is detected, ring detector
circuit 52 signals microcontroller 54 which in turn notifies
computer 16. If so configured, computer 16 then notifies the
user by generating a unique tone to telephone 12 (STEPS 223 &
224), similar to when a computer network call is received
while conducting a public telephone network call, as discussed
above. The user can then switch between the calls using hook
flashes or the GUI (STEPs 213-218), also as discussed above.
When the network call is completed, the user simply hangs up
telephone 12. Off-hook detector circuit 56 senses when the
phone is hung up and sends a signal to microcontroller 54,
which sends a signal to computer 16. Both microcontroller 54
and computer 16 are then reset to their pre-call
configurations.
3. Outaoina Public Telephone Network or Computer Network
Call
The operation for placing an outgoing call varies depending
upon how the user has configured the system 10. Computer 16
and adapter 30 can be configured, using the software resident
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on each, to operate in one of two modes: (1) computer-based
mode; or (2) simulated public branch exchange (PBX) mode.
Both configurations are generically illustrated in Figure 6 as
STEP 301. A detailed description of each configuration is
provided below.
When configured to operate in computer-based mode, the user
first configures computer 16 and adapter 30 for the type of
call being placed using software resident on computer 16. The
user then initiates the call by picking up the telephone 12
receiver and dialing the appropriate telephone number. Thus,
when the user desires to make a public telephone network call,
adapter 30 need not be reconfigured from its normal operating
mode, which allows all telephony signals to pass directly
between telephone 12 and public telephone network 14. To
place a computer network call in this mode, the user
reconfigures adapter 30 using computer 16, such that all
telephony signals are passed between telephone 12 and computer
16. This is accomplished by computer 16 ordering
microcontroller 54 to change the position of switch 44 to
interconnect connection circuitry 38 and line interface
circuit 62. The user then dials the appropriate number of the
party being called, for example the Internet protocol (IP)
address, using software on computer 16. Alternatively, the
user could dial the number using telephone 12. In this case,
DTMF detector circuit 58 detects the digits being dialed and
sends this information to computer 16, via microcontroller 54
and connector 72. Using either method, the client software 92
on computer 16 detects an outgoing network call attempt (STEP
301) .
When the system is configured to operate in the simulated PBX
mode, adapter 30 automatically defaults to connect telephone
12 to public telephone network 14. However, DTMF tone
detector circuit 58 detects the digits the user dials on
telephone 12, and forwards this information, via
microcontroller 54, to computer 16. Based upon the initial
digits dialed, computer 16 determines whether a computer
network call is being placed. If client software 92 detects
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the outgoin~net(w_ork call attempt, computer 16 then _
automatically configures adapter 30 for this purpose. If,
however, a public telephone network call is being placed, then
adapter 30 is not reconfigured.
Subsequent operations carried out by adapter 30 and computer
16 for both a public network telephone call and a computer
network telephone call are the same for both the computer-
based mode and simulated PBX mode. These subsequent
operations will now be discussed.
lr~hen the client software 92 detects the outgoing call attempt
(STEP 301), it is first determined whether a network call is
-. _;.
already taking place (STEP 302). If so, then a message is
displayed on computer 16 alerting the user to this fact (STEP
303). If a network call is not taking place, a determination
is made as to whether a public network call is taking place
(STEP 304). If so, a message informing the user is displayed
on computer 16 (STEP 305). The user can then-use hook flashes
or GUI to place the public network call on hold (STEPs 306 and
307). If the public call is riot placed on hold in a
predetermined period of time. (e.g., 30 seconds), then the
attempted computer network call~is canceled (STEP 308).
If neither a computer network call nor a public network call
r:':~: are taking place, or after the public network call has been
placed on hold (STEP 307), the data path between adapter 30
and computer 16 is opened and the number of the party being
called is then sent out over computer network 18, to the
appropriate IP address. Audio processor 64 can then transmit
the call progress signals, discussed previously, to telephone
12. G~hen the party being called answers, audio processor 64
is configured to transmit, receive, and convert the telephony
signals, as appropriate, between computer network 18 and
telephone 12. Additionally, if the user is making a computer
network call, the user has the option of config~,ring computer
16 and adapter 30 to use the computer's installed sound
peripheries, such as a sound card, microphone, and speakers,
instead of using telephone 12. (All of the foregoing
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functions are accomplished in STEP 309.)
During the network telephone call, adapter 30 continues to
monitor public telephone network 14 for incoming calls (STEPS
310-314). Ring detector circuit 52 monitors connection
circuit 42 for a ring signal from the public telephone network
14 (STEP 312). If a ring signal is detected, ring detector
circuit 52 signals microcontroller 54 which in turn notifies
computer 16. Computer 16 then notifies the user by generating
a unique tone to telephone 12, similar to when a computer
network call is received while conducting a public telephone
network call, as discussed above (STEP 3130. The user can
then switch between the calls using hook flashes or GUI, also
as discussed above (STEPS 315-319).
For both operational modes, when the call is complete the user
hangs up telephone 12. Off-hook detector circuit 56 senses
this condition and sends a signal to microcontroller 54, which
sends a signal to computer 16. Microcontroller 54 and
computer 16 are then reset to their pre-call configurations.
Figure ~ depicts a second embodiment of a system 10
incorporating adapter 30. In the second embodiment, computer
16 is connectable to a computer network 18 using the public
telephone network 14, via a modem (not shown). This
configuration is encountered where the user does not have a
separate connection 23 (see Figure 1) dedicated to connecting
computer 16 to computer~network 18.
In this embodiment, adapter 30 will function as described for
the first~embodiment. However, the user will not be notified
of an incoming computer network call while placing a public
telephone network call, and vice-versa. Thus, the user will
not be able to switch between these platforms in real time.
Additionally, the user will not be alerted to an incoming
computer network call unless computer 16 is conr~,ected to.
computer network 18.
While preferred embodiments of the present invention have been
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illustrated in detail, it is apparent that modifications and
adaptations of the preferred embodiments will occur to those
skilled in the art. However, it will be expressly understood
that such modifications and adaptations are within the spirit(
~ scope of the present invention as set forth in the
following claims.
>.:
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