Abstract:
The present invention is embodied in a telephony device, which can be a cordless handset, for providing two-way and or one-way communication with other audio devices, while retaining the ability to serve as a standard cordless telephone device over a public switched telephone network (PSTN), with the capability of performing both functions simultaneously. The invention provides the user with a cordless (RF) radio frequency communication device that interfaces with a wide variety of audio components and or computer hardware and or software, while retaining the ability to be used simultaneously as a cordless and or hands free telephone. Accordingly, the invention may be in active communication with, but not limited to, a computer, laptop computer or notebook, palm device or Web TV device and or external audio devices.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to the fields of telephonic communications and computer telephony. More precisely, the present invention relates to a telephony device, such as a cordless handset, for providing two-way and or one-way communication with other audio devices, while retaining the ability to serve as a standard cordless telephone device over a public switched telephone network (PSTN), with the capability of performing both functions simultaneously.  
         BACKGROUND OF THE INVENTION  
         [0002]    Cordless or wireless communications may include a computer, laptop computer or notebook, palm device or Web TV device. With the huge popularity and movement in consumer usage in Internet telephony, areas such as voice recognition, home automation (voice commands), Internet navigation, voice controlled computer programs, online instant messengers and online voice mail programs are being incorporated.  
           [0003]    Cordless telephones for example, have become very popular in the consumer marketplace. An example of one is disclosed in U.S. Pat. No. 4,591,661. The invention is a cordless telephone transceiver having a broadcast RF receiver. This invention is designed to connect to PSTN public switched telephone network and has no capability to connect externally to any other audio device.  
           [0004]    A wide selection of cordless telephones, indicate the consumer&#39;s interest in communication mobility. Cordless telephones operate by transmitting an RF radio frequency between a handset and or headset and a base unit, which is connected to a PSTN. The typical handset is equipped with a number pad, for dialing numbers, and a ringer so the user can send and receive, initiate and terminate telephone calls. Other functionality may be incorporated into the terminate telephone calls. Other functionality may be incorporated into the handset and or headset, for example, communication with the base or a paging function initiated from the base to help find the handset or headset. Using RF as its communication link enables the user to roam from room to room and even outside while using the phone. The user is limited to a certain reception area. The consumer market has become very accustomed to the convenience of these devices, and in turn, very familiar with their interface.  
           [0005]    A large percentage of the end user base already use a wired microphone, and or, wired speakers and or, a corded microphone headset. Consequently, software manufactures design their service or product to be pre-configured for these devices. The designs utilize the standard microphone jack or input jack or audio input jack and or speaker jack or output jack or speaker out jack of most audio devices. If the end user was already using a wired or cordless microphone, and or, wired or cordless speakers and or, increasingly popular, corded or cordless (wireless) microphone headset, devices could plug directly into the same jacks that they were already utilized. Other connections are possible and include but are not limited to, USB (universal serial bus) connection, RF (radio frequency) transmitter and or receiver, IR (infrared) transmitter and or receiver, or any other cabled or cordless connections.  
           [0006]    There are many different computer hardware platforms and operating systems. If a nonproprietary interface will work on PC compatible systems as well as, but not limited to, Macintosh computers it will work on any multimedia computer that has the capability of audio input and or audio output (to be fully functional both are required). A device may require software to be loaded in order for it to operate with many different audio devices, or computers with sound cards, audio equipment such as audio recorders and audio players, other telephony equipment or any device that has an audio input and or audio output.  
           [0007]    Therefore what is required is a useful tool that would operate in an already successful market and have at its disposal a way to make existing products even more useful than they already were. What is further required is a less constrictive and less cumbersome method of audio input and or output to a computer.  
           [0008]    A design that will work as a standard cordless telephone as well as a full duplex communication device is required that will interface with a typical sound card enabled computer with a standard Internet connection, and would have the ability to conduct Internet enabled telephone calls using third party software. In addition, what is required is a device that can host an Internet call and a Standard Telephone Call, simultaneously, and can conference call between the Internet Call and the Standard Telephone Call or put one or the other on hold.  
         SUMMARY OF THE INVENTION  
         [0009]    To overcome the limitations in the prior art described above, and to overcome other limitations that will become apparent upon reading and understanding the present specification, the present invention is embodied in a telephony device, which can be a cordless handset, for providing two-way and or one-way communication with other audio devices, while retaining the ability to serve as a standard cordless telephone device over a public switched telephone network (PSTN), with the capability of performing both functions simultaneously.  
           [0010]    The invention provides the user with a cordless (RF) radio frequency communication device that interfaces with a wide variety of audio components and or computer hardware and or software, while retaining the ability to be used simultaneously as a cordless and or hands free telephone.  
           [0011]    Accordingly, the invention may be in active communication with, but not limited to, a computer, laptop computer or notebook, palm device or Web TV device and or external audio devices. Variations of the invention include the following.  
           [0012]    Cordless sound input for use in place of a cabled microphone. The microphone from the handset could be used, or a headset could be plugged into the handset and become hands free Cordless sound output can be used for listening to sound normally heard through external speakers and or pc speaker, stereo or mono headphones, etc. In addition to being a cordless communications device, it can operate as a regular corded or cordless telephone with all the normal features.  
           [0013]    Computer telephony can be implemented with third party computer telephony products, for long distance phone calls in the U.S. and many other countries. Use the invention&#39;s full duplex cordless capabilities with third party software for making computer-to-computer phone calls and n computer to standard phones through public switch telephone network. Additionally, use the invention for checking your on-line voice mail messages. Use the invention with instant messenger services. Use all of these, with cordless freedom.  
           [0014]    Voice recognition can be implemented with third party software for dictation purposes as well as using voice commands with third party software for controlling a computer by giving voice commands, surfing the Internet, giving a presentation to a large audience using a computer driven slide presentation on an LCD projector.  
           [0015]    Home automation with third party software to control domestic applications through voice activation. Conference calling for conducting a standard telephone call. The call can be put on hold, then a computer telephony call can be initiated, and a button can be depressed for a three-way conference call. Telephone call recording for recording live telephone conversations with a telephone call recording feature, digital and or analog, which has audio input and recording capabilities. Examples include, but are not limited to, a computer hard drive, DAT recorder or standard tape recorder.  
           [0016]    A telephone audio playback can be engaged in an active telephone call to include a secondary audio source into the conversation. For instance, during a telephone call, if the user were hooked to a multimedia computer, it would be possible to hear any sound that the computer was making. For example, during an active standard telephone call over a PSTN, a user may want to play a recorded voice mail message from their on line voice messaging service for the person to hear while they are on the telephone with them. This is possible by merely pushing the correct sequence of buttons, so that the secondary audio signal is connected, and then launching the audio file on the computer. It is also possible to adjust the volume of this signal from the computer. It is also possible to introduce the secondary audio signal from a multitude of other audio devices. These following examples include, but are not limited to, personal digital recorder player, compact disk player, DAT recorder &amp; player, etc. It is also possible to connect additional devices simultaneously through the use of normal splitters, adaptors and or cables.  
           [0017]    Cordless public address (PA) can be implemented when used in conjunction with the input of a capable audio device, such as but not limited to an audio amplifier &amp; speakers and or audio receiver and speakers, the invention could be used as a PA public address system. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0018]    The present invention can be further understood by reference to the following description and attached drawings that illustrate the preferred embodiment. Other features and advantages will be apparent from the following detailed description of the preferred embodiment, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.  
         [0019]    [0019]FIG. 1 shows a diagram of preferred embodiment in communication with a standard sound card equipped computer with Internet connection capabilities and typical third party software packages loaded.  
         [0020]    [0020]FIG. 2 shows a diagram of another embodiment being utilized as a normal cordless phone over a (PSTN) public switched telephone network.  
         [0021]    [0021]FIG. 3 shows a diagram of another embodiment being utilized as a normal cordless phone over a (PSTN) public switched telephone network.  
         [0022]    [0022]FIG. 4 shows a diagram of an alternative embodiment of the present invention communicating with other audio signal devices.  
         [0023]    [0023]FIG. 5 shows a diagram of the coupling device for the audio output or Base Line Out.  
         [0024]    [0024]FIG. 6 shows a block diagram of a Base Line Out coupling device.  
         [0025]    [0025]FIG. 7 shows a diagram of the audio input or Base Line In device.  
         [0026]    [0026]FIG. 8 shows a diagram of the voltage regulator used by the coupling device. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0027]    In the following description of the invention, reference is made to the accompanying drawings, which form a part hereof, and in which is shown by way of illustration a specific example in which the invention may be practiced. It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the present invention.  
         [0028]    I. Introduction  
         [0029]    The present invention is embodied in a system and method for a cordless handset to provide two-way and or one-way communication with other audio devices, while retaining the ability to serve as a standard cordless telephone device over a public switched telephone network (PSTN), with the capability of performing both functions simultaneously.  
         [0030]    In general, the present invention provides a means for the user to work with a variety of audio devices, through an interface with a standard computer audio card; more precisely, a computer equipped audio card having the ability to send an audio signal out and as well as being able to accept an external audio signal from another source. This interface provides multiple options using the connection.  
         [0031]    II. General Overview  
         [0032]    [0032]FIG. 1 shows a diagram of a preferred embodiment of the invention. A typical cordless phone  100  with intercom and conferencing capabilities, has two parts, a set  101  and a base unit  104 . The base unit  104 , has a speaker  102  and a microphone  103  that attaches to a phone line  109  and the set  101  which may be a headset or a handset communicating by RF. The system has an intercom mode that allows communication between the base  104  and the set  101 . Also the device can conference between the base  104 , the PSTN  180  and the set  101 .  
         [0033]    In the normal intercom mode, sound detected by the microphone  103  of the base  104  is transmitted to the speaker  191  of the set  091 , and sound detected by the microphone  192  of the set  101  is transmitted to the speaker  102  of the base  104 . A speaker driver  193  drives the speaker  102  in the base  104 , and the microphone  103  is connected to a pre-amplifier. Audio signals in the phone  100  are re-routed so that the phone  100  audio input is enabled through the base line in  106  and audio output is enabled through base line out  107  connections.  
         [0034]    When the phone  100  is in communication with the computer  110  through the computer sound card  116 , the base line in  108  connection receives a signal from the audio output  114  of the computer sound card, and in turn the signal is directed through the microphone pre-amplifier and transmitted to the set  101  earpiece.  
         [0035]    The base line out  107  receives its signal from the base speaker driver  193 , and in turn the signal is sent to the microphone input  115  of the sound card  116 . The signal is attenuated to a level appropriate for the proper input of the connecting device. When the base unit  104  is operating in Mode A, and the user  190  speaks into the set  101  microphone  192 , the resultant audio signal is transmitted to the base in  106 . From here the signal is routed  196  to the line out  107  and into the computer microphone  115 .  
         [0036]    Conversely, any audio signal produced by computer speaker out  114  is transmitted to line in  108  and then through  197  to the base out  105  and to the handset speaker  191 . Audio, transmitted or received by the sound card  116 , could be used, but not limited to, Internet telephony  111 , audio recording/playback  112 , or speech recognition/voice command  113 .  
         [0037]    Audio signals, sent and received from the base line in  108 , and out  107 , could be transmitted by the computer, using Internet telephony software  111 , through the Internet  140  to an Internet telephony provider  150 . The provider  150  could call a remote telephone user  170  through the PSTN  160 . The result would be full duplex communication between the user  190  and the remote telephone user  170 .  
         [0038]    III. Details of the Components and Operation  
         [0039]    In mode A, running audio recording software  112 , would allow the user&#39;s voice to be recorded via the set  101 . In addition, audio could be played back to the user  190  from the computer  110  through the set  101 . Operating in mode A and running speech recognition/voice command  113  on the computer  110 , would allow the user  190  to control the computer  110 , or any other device attached to the computer  110 , for example home automation devices  120 , by audio.  
         [0040]    [0040]FIG. 2 shows a diagram of a preferred embodiment of the present invention in mode B. This mode allows the invention to operate as a standard cordless phone. The audio generated by the user  190  through the microphone  192  is transmitted via RF to the base unit&#39;s  104  reception circuitry, base in  106  and then through the phone line interface  109 . Inbound audio from the phone line in  108  is transmitted to the base out  105  and thence via RF to the set speaker  191 . Additionally DTMF tones can be generated to allow dialing of phone numbers.  
         [0041]    [0041]FIG. 3 shows a diagram of a preferred embodiment labeled mode C. In this mode the invention allows for communication with devices linked through the base unit&#39;s line in  108 , line out  107 , RF in  106 , RF out  105 , and the phone line. When the user  190  generates audio through the microphone  192 , it is transmitted  391 ,  393 , through the base in  106  to the phone line interface  109  and the line out  107 .  
         [0042]    When the audio is generated from the phone line interface  109 , it is conducted  395 ,  396  to the base out  105  and the base line out  107 . When audio is generated from the computers speaker  114 , it is conducted to the base line in  108 , and then via  392  to the phone line interface  109 , and by  393  to the base RF out  105 . From there it is transmitted to the set  101  for playback on the speaker  191 . This allows full duplex conferencing between the computer  110  and the user  190 , an Internet telephony caller  170  and a regular PSTN caller  181 . Recordings or plays back (through  112 ) of telephone calls between users could be made.  
         [0043]    [0043]FIG. 4 shows a diagram of a secondary embodiment of the invention. The phone  100  has the capacity to operate with standard audio recording and playback devices  410 , as well as to act as a telephone. This means that conversations could be recorded and played back, playback recorded audio into a telephone conversation, or play a telephone conversation live over an audio sound system. The set  101  could be used to record the user&#39;s  190  voice for purposes such as dictation.  
         [0044]    II. Working Example  
         [0045]    FIGS.  5 - 8  show diagrams of a working example of a coupling device for the audio output described in FIGS.  1 - 4  as base line out  105 . To achieve the desired connectivity, additional circuitry to the phone to enable desired impedance matching was used. The circuitry of FIGS.  5 - 8  illustrate just an example to enable the utilization of an existing phone product to act functionally. The circuit is referred to as the “Coupling Device”.  
         [0046]    The coupling device allows the speaker driver  193  of the phone to drive the microphone inputs  115  of the computer&#39;s sound card. The (35 ohm) speaker of the phone was disconnected to allow easy connection to the coupling device, and a (33 ohm) resistor  510  was added across the differential inputs of the coupling device. This resistor  510  prevents the absence of the speaker from significantly affecting the operation of the speaker driver  193 . The coupling device isolates the phone from the sound card  116 , attenuates the signal to levels appropriate for the microphone input  115 , and was designed so it can use power from the phone.  
         [0047]    A voltage divider made from (fixed-value) resistors was used to attenuate the signal from the speaker-out  114  output, of the sound card  116 , on its way to the microphone preamplifier of the phone. It was found that the negative terminal of the preamplifier did not need to be connected to this voltage divider because the phone internally connects this negative terminal to one terminal of its speaker driver. Since the coupling device includes a resistor  512  between that terminal of the driver and the ground of the sound card, the needed connection is already (indirectly) supplied.  
         [0048]    The voltage divider extends from one of the stereo channels (either the left or the right channel) of the speaker-out jack of the sound card  116  to the ground of the same jack. The other channel is not used. The positive input of the phone&#39;s microphone preamplifier is connected to a point between the two resistors of the voltage divider. Thus, the signal from the sound card  116  is attenuated before the preamplifier. The phone internally provides the connection between the negative terminal of the preamplifier and the terminal of the phone&#39;s speaker driver that is connected to the In  1  (−)  502  input of the coupling device.  
         [0049]    The coupling device was connected, almost directly to the phone&#39;s DC power plug. As the DC power provided by the plug was rough a filter was added, and voltage regulated between this plug and the coupling device. The phone may provide filtering and voltage regulation internally and some internal point for powering to the coupling device may be able to be connected. The 33□ohm resistor and the capacitors shown in FIG. 8 provide the filtering. The voltage regulator (for example, it can be ML 7805A)  810  maintains its output at five volts above the regulators reference terminal. Two resistors function as a voltage divider to raise the reference potential about 4.1 volts above the negative terminal so the output is about 9.1 volts above the negative terminal.  
         [0050]    The phone&#39;s speaker driver  193  is connected to the inputs In  1  (−)  502  and In  2  (+)  504 . The resistor R 6   510  prevents the absence of the speaker from significantly affecting the operation of the speaker driver. High-pass filters (capacitor C 1   514  and, resistor R 3   516 ) filter away DC offsets. The operational amplifiers A 1   518  and A 2   520  function as voltage followers to provide isolation from the differential amplifier that is at their outputs. This differential amplifier (including A 3 ,  522 ) actually provides the attenuation down to levels appropriate for the microphone inputs of the sound card  116 . The output of this differential amplifier passes through another high-pass filter that provides some isolation from the sound card.  
         [0051]    Since three voltages power this coupling device, but the phone provides two voltages, amplifier A 4   524  is part of an averager that supplies a middle voltage. Additional capacitors (four of them) are connected to the power inputs to diminish the effects of transients. The example used a quad op amp chip (LM 324 N)  526  to provide all four operational amplifiers.  
         [0052]    The foregoing has described the principles, preferred embodiments and modes of operation of the present invention. However, the invention should not be construed as being limited to the particular embodiments discussed. The above-described embodiments should be regarded as illustrative rather than restrictive, and it should be appreciated that variations may be made in those embodiments by workers skilled in the art without departing from the scope of the present invention as defined by the following claims.