Title: Cordless telephone system with wireless expansion peripherals
Abstract: A cordless telephone system comprising a base unit, at least one handset, and one or more expansion units is provided. The handset and the expansion units communicate with the base unit via communication channels implemented in a wireless communication protocol. The expansion units can provide the system with communication interfaces to various external networks, such as an additional analog telephone line, a digital telephone line, or a cellular telephone. Conference calling functionality is provided between handsets and expansion base units within the primary base unit. Data services can also be provided by a wireless expansion base unit.
Patent Number: 6,990,356 Issued on 01/24/2006 to Charney, et al.
| Inventors:
|
Charney; Douglas (Richmond, CA);
Ryley; Gordon (Calgary, CA)
|
| Assignee:
|
VTech Telecommunications, Limited (Tai Po, HK)
|
| Appl. No.:
|
338574 |
| Filed:
|
January 8, 2003 |
| Current U.S. Class: |
455/552.1; 455/550.1; 455/553.1; 455/465; 455/463; 455/462; 379/419; 379/440 |
| Current Intern'l Class: |
H04M 1/00 (20060101) |
| Field of Search: |
455/5521,550.1,465,432.1,73,741,553.1,463,462,419,440
|
References Cited [Referenced By]
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| 2003/0003917 | Jan., 2003 | Copely et al.
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| 2003/0078071 | Apr., 2003 | Uchiyama.
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| 2004/0097259 | May., 2004 | Toor et al.
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| Foreign Patent Documents |
| 0 849 965 | Dec., 1996 | EP.
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| GB SEARCH REPORT | Jun., 2004 | GB.
| |
| WO 2004/025928 | Mar., 2004 | WO.
| |
Primary Examiner: Trinh; Sonny
Assistant Examiner: Nguyen; Khai
Attorney, Agent or Firm: Pillsbury Winthrop Shaw Pittman LLP
Claims
We claim:
1. A cordless telephone system comprising:
a primary cordless telephone base unit coupled to a primary communications network
and implementing a wireless communication protocol capable of supporting simultaneous
communications via a plurality of wireless communications channels;
a cordless telephone handset;
a first communication link between the handset and the primary cordless telephone
base unit, the communication link being established using a first one of the plurality
of wireless communication channels;
an expansion base unit, the expansion base unit comprising a first communication
interface linking the expansion base unit to an external communication network,
and a second communication interface compatible with the wireless communication protocol;
a second communication link between the primary cordless telephone base unit
and the second communication interface of the expansion base unit, the communication
link being established using a second one of the plurality of wireless communication channels;
whereby the cordless telephone system transmits voice information between the
cordless telephone handset and the expansion base unit via the first communication
link, the primary cordless telephone base unit, and the second communication link.
2. The cordless telephone system of claim 1, in which the expansion base unit
first communication interface is comprised of an analog telephone line interface;
whereby the cordless telephone handset can place or receive telephone calls via
the expansion base analog telephone line.
3. The cordless telephone system of claim 1, in which the expansion base unit
first communication interface is comprised of a cellular telephone interface adapted
for communications with a cellular telephone; and the external communication network
to which the expansion base unit is linked comprises a cellular telephone network;
whereby the cordless telephone handset is capable of placing and receiving calls
via the expansion base unit and the cellular telephone network when the cellular
telephone is engaged with the cellular telephone interface.
4. The cordless telephone system of claim 1, in which the expansion base unit
first communication interface is comprised of a digital telephone line interface;
whereby the cordless handset can place or receive telephone calls via the expansion
base digital telephone line.
5. The cordless telephone system of claim 1, in which the expansion base unit
first communication interface is comprised of a digital data network interface
configured to communicate with a data network; whereby digital data services can
be provided to the cordless handset via the expansion base unit and the data network.
6. The cordless telephone system of claim 5, in which the first communication
interface is comprised of a wireless digital data network interface configured
to communicate with a wireless access point, whereby digital data services can
be provided to the cordless telephone handset via the expansion base unit and the
wireless data network.
7. The cordless telephone system of claims 1, in which the primary base unit
is further comprised of:
a primary telephone line interface adapted for communications via a primary telephone line;
a radio transceiver adapted to conduct simultaneous communications via the first
communication link and the second communication link;
a baseband audio processor configured to combine audio signals received from
the radio transceiver and the primary telephone line interface; whereby conference
calling can be implemented between the cordless handset, the external communication
network to which the expansion base unit is connected, and the primary telephone
line interface.
8. A cordless telephone system comprising:
a primary cordless telephone base unit implementing a wireless communication
protocol capable of supporting simultaneous communications via a plurality of wireless
communication channels;
one or more cordless telephone handsets, each cordless telephone handset having
a wireless communication link with the primary base unit implemented using the
wireless communication protocol;
one or more expansion base units, the expansion base units each comprising an
expansion communication interface linking the expansion base unit to an external
communication network, and a wireless communication link with the primary base
unit using the wireless communication protocol;
the primary cordless telephone base unit being further comprised of:
a radio transceiver capable of conducing simultaneous communications with each
of the one or more handsets and the one or more expansion base units via their
respective wireless communication links;
a baseband audio processor configured to combine audio signals received via two
or more of the wireless communication links;
whereby conference calling can be implemented between two or more of the cordless
handsets and extension base units.
9. The cordless telephone system of claim 8, the primary base unit further comprising:
a microcontroller operably connected with the baseband audio processor, which
microcontroller configures the baseband audio processor to select which audio signals
from the two or more communication links are combined by the baseband audio processor.
10. A cordless telephone teleconferencing system, comprising:
a primary cordless telephone base unit, the base unit connected to a primary
communications network, the base unit implementing a wireless communication protocol
capable of supporting simultaneous communications via a plurality of wireless communication channels;
one or more cordless telephone handsets, each cordless telephone handset having
a wireless communication link with the primary base unit implemented using the
wireless communication protocol;
one or more expansion base units, the expansion base units each comprising an
expansion communication interface linking the expansion base unit to a respective
external communication network, and a respective wireless communication link with
the primary base unit using the wireless communication protocol;
wherein one or more users of the one or more cordless handsets can conduct a
teleconference call simultaneously over the primary communications network and
the external communications network.
11. The cordless telephone teleconferencing system of claim 10, wherein the primary
communications network is a PSTN network.
12. The cordless telephone teleconferencing system of claim 10, wherein each
respective external communications network is one of
a PSTN network;
an ISDN network;
a cellular telecommunications network;
a local area network; and
a wireless data network.
13. The cordless telephone teleconferencing system of claim 10, wherein the wireless
communications protocol is a DECT protocol.
14. The cordless telephone teleconferencing system of claim 10, further comprising
a baseband audio processor configured to combine audio signals received via two
or more of the wireless communication links.
15. The cordless telephone teleconferencing system of claim 14, wherein the baseband
audio processor mixes signals received from multiple cordless handset users and
external users, the external users linked respectively to the primary base unit
over the primary communications network and a plurality of external communications channels.
Description
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates generally to cordless telephone systems. In particular,
the invention relates to a cordless telephone system capable of modular expansion
of its features and capabilities through the addition of wireless peripherals.
2. Background Art
Cordless telephone devices have become increasingly popular among individuals
both at home and in the workplace. Modern cordless telephones offer a wide range
of features. While conventional cordless telephones provide a base unit which communicates
with a single cordless telephone handset, many modern systems provide for expansion
in the number of handsets that may be utilized with a cordless telephone base unit.
The heart of typical existing cordless telephone systems is the cordless telephone
base unit. The base unit typically determines which features are provided by the
cordless telephone system. Features typically dictated by the base unit include
the number of telephone lines to which the system can be connected, the number
of handsets that can be used, and whether ISDN telephone lines can be accessed.
Some base units which have recently been discussed further include an interface
to a cellular telephone. Such a base unit is described in Published U.S. Application
No. 20020072390A1, assigned to Meridian Concepts L.L.C. If a user desires features
that are not provided by the user's current base unit, the user typically must
replace the entire cordless telephone system to upgrade to a system having the
desired features.
Outside the realm of consumer cordless telephones, expandable telephone systems
are known in the private branch exchange ("PBX") art. Typically such systems include
a main PBX unit having a plurality of physical slots which can be optionally populated
by additional line interface circuit boards to increase the capacity of the system.
However, the increased size of the primary base unit caused by provision of physical
expansion slots may be highly undesirable in some applications. Furthermore, extra
cost is incurred by providing the connectors and other hardware required to support
the electrical interfaces to potential expansion units. When expansion devices
are added to such a system, they typically must be collocated with the main base
unit and sometimes require expert technicians to reprogram and/or configure the
modified system, limiting the flexibility of the system configuration and potentially
incurring extra costs in routing multiple communications lines to the single main
unit location and technical support.
SUMMARY OF THE INVENTION
The present invention provides for the addition of expansion peripherals wirelessly
connected to the base unit of a cordless telephone system. In accordance with one
aspect of the invention, the cordless telephone system includes a primary base
unit that implements a wireless communications protocol capable of supporting simultaneous
communications via a plurality of communication channels. The system further includes
a cordless telephone handset capable of communicating with the primary base unit
via a first communication link established using a first one of the plurality of
communication channels.
An expansion base unit is also provided. The expansion base unit includes a communication
interface linking the expansion base unit to an external communication network.
Expansion base units can be provided to enable communication with a variety of
different networks, such as networks including an analog telephone line, a digital
telephone line, or a cellular telephone network. The expansion base unit communicates
with the primary base unit via a second communication link established using a
second one of the plurality of wireless communication channels. The system provides
the cordless telephone handset with the capability of conducting communications
using the external communications network to which the expansion base interfaces.
In accordance with another aspect of the invention, an expandable conference
calling
feature can also be implemented using the cordless handsets, the primary base unit,
and any expansion peripherals that are available to the system. A radio transceiver
is provided within the primary base unit which conducts wireless communications
with the cordless telephone handsets and any available expansion peripherals. The
audio information received by the radio transceiver is conveyed to a baseband audio
processor, also within the primary base unit. The baseband audio processor is also
configured to receive audio signals from a telephone line interface implemented
within the primary base unit. A microcontroller is provided within the primary
base unit to effect the initiation of conference calling functionality. In so doing,
the baseband audio processor is configured to combine the audio signals appearing
on two or more of the communication channels such that conference calling functionality
is provided.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a prior art cordless telephone system.
FIG. 2 is a block diagram of a cordless telephone system according to one embodiment
of the present invention.
FIG. 3 is a block diagram of a cordless telephone system configuration having
conference calling functionality.
FIG. 4 is a block diagram of a cordless telephone system configuration providing
data services.
DETAILED DESCRIPTION OF THE DRAWINGS
While this invention is susceptible to embodiment in many different forms,
there are shown in the drawings and will be described in detail herein several
specific embodiments, with the understanding that the present disclosure is to
be considered as an exemplification of the principle of the invention and is not
intended to limit the invention to embodiments illustrated.
FIG. 1 illustrates a typical prior art cordless telephone system which is expandable
to accommodate multiple handsets. Base unit
100 implements a multi-channel
wireless communications protocol such that it is capable of communicating with
cordless telephone handsets
110 and
130 via wireless communication
links
120 and
140, respectively. Base unit
100 is provided
with a telephone line interface for one POTS telephone line. If the owner of base
unit
100 desires to implement a two-line telephone system, base unit
100
(and possibly handsets
110 and
130) typically must be replaced in
their entirety with a system having a base unit with two telephone line interfaces
and handsets with two-line capability.
FIG. 2 illustrates a cordless telephone system in accordance with an embodiment
of the present invention. Primary cordless telephone base unit
200 includes
a connection to a single POTS telephone line
210. Primary base unit
200
communicates with cordless telephone handsets
220 and
240 via wireless
communication links
230 and
250, respectively.
The system of FIG. 2 is further provided with the capability of adding expansion
peripherals to increase the functionality of the system. The peripherals are connected
to primary base unit
200 via further channels provided by the wireless communications
protocol with which links
230 and
250 are implemented. Thus, the
interface to expansion peripherals is accomplished primarily using electronic hardware
which is already existent in the base unit. Further connectors and interconnection
components need not be included in base unit
200, saving cost and reducing
the physical size of the base unit.
One type of expansion peripheral provided by the system of FIG. 2 is cellular
base unit
260. Cellular base unit
260 includes a cradle in which
cellular telephone
265 can be placed. Cellular base
260 communicates
with primary cordless base
200 via wireless communication link
270.
Cellular base
260 further includes a wired interface with cellular telephone
265 when cellular telephone
265 resides in the cellular cradle, through
which cellular telephone
265 can be controlled to conduct communications
via cellular telephone infrastructure
330. While cellular base unit
260
is illustrated having a cradle providing physical interconnection with a cellular
telephone, it is understood that other types of communication interfaces between
the cellular base unit and a cellular telephone can readily be implemented. For
example, an interface could be implemented using Bluetooth or infrared wireless
communication capabilities of some cellular telephones.
Integration of a cellular telephone interface to a cordless telephone
system via a wireless link not only provides convenient and cost-effective expandability,
but also provides flexibility in the physical placement of the cellular telephone
while cradled. This can be particularly important inasmuch as the quality of cellular
coverage may vary substantially between various locations inside the user's residence
or office. The optimum location for cellular telephone coverage may not be near
a telephone jack, which is typically required for placement of a primary base unit.
By integrating the cellular cradle with the cordless telephone system via wireless
link
270, the user is provided with the ability to position the cellular
base unit
260 in a location which provides optimum reception quality and
is independent from the location of primary cordless base unit
200 and conventional
telephone line
210.
In operation, a telephone call can be placed from cordless handset
220
via the cellular telephone network using the system of FIG. 2. Primary cordless
base unit
200 detects the presence of cellular base unit
260 having
cellular telephone
265 present and cradled. Primary cordless base
200
transmits a message to cordless handset
220 via communication link
230
indicating that a cellular interface is available for placement of a telephone
call. Cordless handset
220 indicates that the cellular interface is available
via its user interface. The cellular interface can then be selected, and a call
can be dialed, using the cordless handset.
A sequential chain of communications is set up between handset
220, communication
link
230, primary base unit
200, communication link
270, cellular
base
260, and cellular telephone
265. Cellular base
260 provides
the electrical interface with cellular telephone
265, whereby messages from
the cordless telephone system are adapted to a signaling protocol compatible the
cellular telephone interface. Cellular base
260 may further provide echo
cancellation functionality that may be desirable to compensate for the additional
level of delay typically found when communicating over a cellular interface. Primary
cordless base unit
200 provides the communications interface with the cordless
handsets present in the system, and directs signaling to the appropriate handset
when an incoming call is answered or an outgoing call is placed.
Further functionality can be provided by different types of wireless expansion
peripherals. For example, operation in connection with a second POTS telephone
line is provided by expansion base unit
280. Expansion base unit
280
is connected to, and provides an interface for, POTS line
300. In operation,
expansion base
280 transmits a signal to primary base unit
200 via
communication link
290 indicating that it is present and connected to an
active telephone line. Primary base unit
200 then transmits a message to
handsets
220 and
240 via links
230 and
250, respectively,
indicating that line
300 is available for use. The availability of line
300 is indicated by the user interface of each handset. A handset user can
then select line
300 for placement of a telephone call via the handset user
interface. When a telephone call is placed, expansion base
280 serves as
the interface to line
300. Messaging and audio data is conveyed sequentially
between expansion base
280, primary base unit
200, and the active handset.
The system of FIG. 2 further includes the ability to interface with other types
of communications lines. ISDN base unit
340 provides the cordless telephone
system with an interface to digital ISDN telephone line
350. ISDN base unit
340 operates analogously to expansion base unit
280, except that
it provides a telephone line interface compatible with digital ISDN standards.
By routing the wireless peripheral communications through primary cordless base
unit
200, various conference calling features can be readily implemented.
A conference calling arrangement according to one embodiment of the invention is
illustrated in FIG. 3. Primary base unit
200 includes radio transceiver
202 capable of simultaneous communication over communication links
250
and
290. Such multi-channel communications systems are known in the art.
For example, the system of FIGS. 2 and 3 could be implemented using the DECT communications
standard. Each of communication links
230,
250,
270,
290
and
370 could be implemented using a separate time slot on a DECT communications channel.
During a conference call operation, the audio signals corresponding to each
communication channel involved in the conference can be combined within primary
base unit
200. Specifically, radiofrequency signals received at antenna
201 are conveyed to transceiver
202. Baseband audio information is
further conveyed from transceiver
202 to baseband audio processor
203.
Base unit
200 further includes telephone line interface
205, connected
to telephone line
210. Baseband audio processor
203 is further configured
to communicate audio information to and from telephone line interface
205.
A conference call can be set up by handset
240 according to user interface
operations known in the art. Control data initiating the conference call is conveyed
via communication link
250 to transceiver
202 and to microcontroller
204. Microcontroller
204 configures primary base unit
200
to implement the conference calling operation. In so doing, baseband audio processor
203 is configured to combine the audio signals from telephone line interface
205, as well as the audio signals on communication links
250 and
290 received via transceiver
202. In this way, handset
240,
expansion base unit
280 connected to external network
300, and telephone
line
210 can all be readily combined to implement three-way conference calling
functionality. Furthermore, the conference calling capability of the cordless telephone
system can be further expanded to include any additional expansion peripherals
that are present in the system up to the maximum number of peripherals which the
radio interface of primary base unit
200 is capable of supporting simultaneously,
without substantive changes in the base unit hardware.
The present invention can also be employed to provide data services to the cordless
telephone system via a wireless expansion peripheral. Many cordless telephone communication
protocols, such as DECT, provide for the implementation of data services. FIG.
4 illustrates a cordless telephone system arrangement whereby the data services
are provided through a wireless expansion peripheral, such that the data services
can be added to a cordless telephone system centered around a primary base unit
that lacks a data network interface circuit. Elements of FIG. 4 having a prime
(′) following their reference numerals are analogous to the elements of
the preceding drawings having the same number without a prime (′). Network
expansion base unit
460 provides a data network adapter connected to local
area network ("LAN")
470. Data communications received from LAN
470
by expansion base unit
460 are conveyed to primary base unit,
200′.
Such data communications can then be relayed to the cordless telephone handsets,
as appropriate for a desired data application. While network expansion base unit
470 is illustrated as communicating via an ethernet-type data connection,
it is understood that other data connections could also be readily provided by
wireless expansion base units in accordance with the invention, such as a broadband
cable data network interface or DSL.
Data services can also be provided by the cordless telephone system of FIG.
4 via a wireless data network, such as a wireless LAN
480 implemented using
the IEEE 802.11 ("Wi-Fi") wireless networking protocol. Wi-Fi base unit
440
includes a Wi-Fi transceiver capable of communicating with access point
410.
Access point
410 is interconnected with wired LAN
420. Data can be
relayed between access point
410, wireless LAN
480, Wi-Fi expansion
base unit
440, communication link
430, primary base unit
200′,
and cordless handsets
220′ and/or
240′ via links
230′
and/or
250′, respectively. In this way, access to wireless LAN
480
is provided to enable implementation of data services within the cordless telephone
system, without requiring the provision of a data network interface in primary
base unit
200′.
The foregoing description and drawings merely explain and illustrate the invention
and the invention is not limited thereto except insofar as the appended claims
are so limited, inasmuch as those skilled in the art, having the present disclosure
before them will be able to make modifications and variations therein without departing
from the scope of the invention.
*
