Abstract:
A method for providing battery charge current to a portable electronic device having a rechargeable battery. The method includes the steps of providing a power adaptor which connects to a power supply and converts power from the power supply into a battery charge current; providing a cable operative to deliver the battery charge current from the power adaptor to the portable electronic device to charge the rechargeable battery; and providing radio frequency (RF) signals induced onto the cable to an RF receiver input.

Description:
TECHNICAL FIELD OF THE INVENTION 
       [0001]    The present invention relates generally to portable electronic devices, and more particularly to rechargeable portable electronic devices. 
       DESCRIPTION OF THE RELATED ART 
       [0002]    Portable electronic devices have been popular for decades, and continue to increase in popularity. Many modern portable electronic devices are intended or suitable for recording or playback of acoustic and/or video signals. For example, portable CD or DVD players, MPEG players, MP-3 players, etc. provide a vast variety of forms of personal entertainment. Whether audio and/or video entertainment, there are numerous portable electronic devices to satisfy any user&#39;s tastes. 
         [0003]    Similarly, portable electronic devices in the form of mobile phones, pagers, communicators, e.g., electronic organizers, personal digital assistants (PDAs), smartphones or the like are also becoming increasingly popular. Such devices allow a user to communicate with others, store and manipulate data, create text, etc., many times within the same device. 
         [0004]    Although portable radios per se have been available for many years, nowadays more and more other types of portable electronic devices, e.g., mobile phones, pagers, PDAs, etc., have been designed also to include a radio function. For example,  FIG. 1  illustrates a conventional mobile phone  10  for use in mobile communication systems such as cellular networks, satellite networks, etc. The mobile phone  10  includes a built-in AM/FM radio receiver (not shown) that enables the mobile phone  10  to receive AM/FM radio broadcasts. 
         [0005]    The user may listen to the radio broadcasts via a headset  12  having a pair of earbuds  14  or the like. The earbuds  14  are connected to the mobile phone  10  via a wire or cable  16  and headset connector  18 . The radio receiver within the mobile phone  10  receives and demodulates AM/FM broadcast signals. The mobile phone  10  outputs the resultant audio signals (mono or multi-channel) to the headset  12  so that the user may listen to the radio broadcasts using the earbuds  14 . 
         [0006]    In the case of the mobile phone  10 , the built-in antenna used in carrying out mobile communications is designed for frequencies much higher than AM/FM or other lower frequency radio signals. Consequently, the built-in antenna is not suitable for receiving AM/FM broadcast signals. In the case of other types of portable electronic devices, e.g., PDAs, CD players, etc., the portable electronic device may not include any type of built-in antenna whatsoever. Accordingly, such devices frequently use the cable  16  of the headset  12  as an antenna. The mobile phone  10  or other type of electronic device includes sense circuitry therein that detects that a headset  12  has been connected to the device. The mobile phone  10  or other device is configured to detect the presence of the headset  12  and thereby enable operation of the radio receiver using the cable  16  as an AM/FM antenna as represented in  FIG. 1 . 
         [0007]    Despite the benefits of using the headset cable as an antenna, there have been various drawbacks associated with such conventional design. For example, a headset for a mobile telephone or other type portable electronic device typically connects to the device via a multifunction connector (not shown) included in the device. The multifunction connector not only allows a headset to be coupled to the device, but also allows other types of accessories to be connected to the device. This is disadvantageous in that while another accessory is connected to the mobile phone or other type device via the multifunction connector, it is impossible to connect the headset to the device. As a result, without the antenna it becomes impossible for a user to listen to radio broadcasts while the other accessory is connected to the device. 
         [0008]    For example,  FIG. 2  shows a power adaptor  20  for charging a rechargeable battery (not shown) included in the mobile phone  10 . The power adaptor  20  includes a connector  22  that is designed to connect to the same multifunction connector included in the mobile phone  10  as the connector  18  of the headset  12 . Thus, if the user is utilizing the mobile phone  10  to listen to the radio via the headset  12 , the user is unable to connect the mobile phone  10  to the power adaptor  20  in order to simultaneously charge the battery in the mobile phone  10 . Conversely, if the user is charging the mobile phone  10  using the power adaptor  20 , the user cannot simultaneously listen to radio broadcasts. 
         [0009]    In view of the aforementioned shortcomings associated with conventional portable devices using a headset cable as an antenna, there is a strong need in the art for a device and system that will allow a user to listen to radio broadcasts even when the portable device is being recharged. 
       SUMMARY 
       [0010]    According to an aspect of the invention, a method is directed to providing battery charge current to a portable electronic device having a rechargeable battery. The method includes the steps of providing a power adaptor which connects to a power supply and converts power from the power supply into a battery charge current; providing a cable operative to deliver the battery charge current from the power adaptor to the portable electronic device to charge the rechargeable battery; and providing radio frequency (RF) signals induced onto the cable to an RF receiver input. 
         [0011]    According to a particular aspect of the invention, the cable connects to the portable electronic device, and the portable electronic device comprises decoupling circuitry operative to decouple the RF signals from the cable and to provide the RF signals to the RF receiver input, the RF receiver input being included in the portable electronic device. 
         [0012]    In accordance with another aspect of the invention, the decoupling circuitry comprises a decoupling capacitor. 
         [0013]    According to yet another aspect, the decoupling circuitry blocks DC components on the cable from being input to the RF receiver input. 
         [0014]    According to still another aspect, an accessory is coupled to the cable and provides the battery charge current to the portable electronic device, the accessory comprising decoupling circuitry operative to decouple the RF signals from the cable and to provide the RF signals to the RF receiver input. 
         [0015]    In accordance with another aspect, the RF receiver input is included in the portable electronic device. 
         [0016]    According to another aspect, the accessory is a docking station for use when charging the rechargeable battery in the portable electronic device. 
         [0017]    According to yet another aspect, the RF receiver input is included in the accessory. 
         [0018]    According to still another aspect, the accessory further includes an audio amplifier for amplifying audio signals output from the RF receiver included within the accessory. 
         [0019]    In accordance with another aspect, the accessory further includes at least one speaker for reproducing the audio signals. 
         [0020]    In accordance with still another aspect, the cable is coupled to at least one inductor for isolating the cable from system ground at frequencies of the RF signals. 
         [0021]    According to a different aspect of the invention, a portable electronic device is provided that includes a rechargeable battery; a radio receiver including an RF receiver input; an input for receiving a battery charge current from a cable operative to deliver the battery charge current from a power adaptor to the portable electronic device in order to charge the rechargeable battery; and decoupling circuitry operative to decouple RF signals induced onto the cable and to provide the RF signals to the RF receiver input. 
         [0022]    According to another aspect, the decoupling circuitry comprises a decoupling capacitor. 
         [0023]    In accordance with another aspect, the decoupling circuitry blocks DC components on the cable from being input to the RF receiver input. 
         [0024]    With yet another aspect according to the present invention, a docking station for docking a portable electronic device having a rechargeable battery in order to recharge the rechargeable battery. The docking station includes an input for receiving a battery charge current from a cable operative to deliver the battery charge current from a power adaptor to the portable electronic device via the docking station in order to charge the rechargeable battery; and decoupling circuitry operative to decouple RF signals induced onto the cable and to provide the RF signals to an RF receiver input. 
         [0025]    According to another aspect, the RF receiver input is included in the portable electronic device. 
         [0026]    According to still another aspect, the docking station includes an audio amplifier for amplifying audio signals output from the RF receiver included within the portable electronic device. 
         [0027]    According to but another aspect, the docking station further includes at least one speaker for reproducing the audio signals. 
         [0028]    In yet another aspect, the RF receiver input is included in the docking station. 
         [0029]    In still another aspect, the docking station further includes an audio amplifier for amplifying audio signals output from the RF receiver included within the docking station. 
         [0030]    With yet another aspect, the docking station further includes at least one speaker for reproducing the audio signals. 
         [0031]    In another aspect, the cable is coupled to at least one inductor for isolating the cable from system ground at frequencies of the RF signals. 
         [0032]    To the accomplishment of the foregoing and related ends, the invention, then, comprises the features hereinafter fully described and particularly pointed out in the claims. The following description and the annexed drawings set forth in detail certain illustrative embodiments of the invention. These embodiments are indicative, however, of but a few of the various ways in which the principles of the invention may be employed. Other objects, advantages and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the drawings. 
         [0033]    It should be emphasized that the term “comprises/comprising” when used in this specification is taken to specify the presence of stated features, integers, steps or components but does not preclude the presence or addition of one or more other features, integers, steps, components or groups thereof. 
     
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0034]      FIG. 1  illustrates a conventional portable electronic device, in the form of a mobile phone, together with a headset; 
           [0035]      FIG. 2  illustrates the conventional portable electronic device of  FIG. 1  together with the headset and a power adaptor for recharging a battery included in the portable electronic device; 
           [0036]      FIG. 3  illustrates a portable electronic device, in the form of a mobile phone, together with a power adaptor in accordance with an embodiment of the present invention; 
           [0037]      FIG. 4  is a block diagram of the portable electronic device of  FIG. 3  in accordance with the present invention; 
           [0038]      FIG. 5  illustrates a portable electronic device, in the form of a mobile phone, together with a power adaptor with docking station in accordance with another embodiment of the present invention; 
           [0039]      FIG. 6  is a block diagram of the docking station of  FIG. 5  according to a particular embodiment of the present invention; and 
           [0040]      FIG. 7  is a block diagram of the docking station of  FIG. 5  according to another particular embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF EMBODIMENTS 
       [0041]    The present invention will now be described with reference to the drawings, wherein like reference numerals are provided for like elements throughout. 
         [0042]    According to the present invention, a portable electronic device functions to receive and play radio signals (e.g., AM/FM broadcast signals) even in the event the portable electronic device is simultaneously being recharged. The portable electronic device can receive and play the radio signals, regardless of whether the portable electronic device typically utilizes a multifunction connector that cannot simultaneously connect the device to a headset and power adaptor. 
         [0043]    Referring to  FIG. 3 , a first embodiment of the present invention is illustrated. The portable electronic device is, for sake of example, a mobile phone  30  that includes a radio frequency (RF) receiver therein (not shown). Unlike the conventional mobile phones discussed above, however, the mobile phone  30  can receive and play AM/FM radio broadcasts even while the battery (not shown) within the mobile phone  30  is being recharged via the power adaptor  20 . 
         [0044]    More specifically, the present invention utilizes a cable  32  of the power adaptor  20  as an antenna for the radio receiver within the mobile phone  30 . As a result, the mobile phone  30  need not rely exclusively on the cable of the headset  16  as an antenna in order to receive radio signals. 
         [0045]    The power adaptor  20  includes a plug  34  that plugs into a power supply such as a wall outlet  36 , automobile cigarette lighter-type power jack, etc. As is conventional, the power adaptor  20  includes circuitry (not shown) within the plug  34  for converting the power supply voltage (e.g., 120VAC, 12VDC, etc.) to a low-voltage DC battery charge current. The plug  34  provides the battery charge current via the multiconductor cable  32  to the mobile phone  30 . (It will be appreciated that throughout the present description multiconductor connections are at times represented by a single line in the drawings for sake of simplicity.) 
         [0046]    As noted above, the power adaptor  20  is connected to the mobile phone  30  by way of a connector  22  at the end of the cable  32  being connected to the multifunction connector (not shown) included in the mobile phone  30 . The power adaptor  20  provides the battery charge current via the cable  32  to charge up a rechargeable battery included in the mobile phone  30 . 
         [0047]    The mobile phone  30  includes otherwise conventional sense circuitry (not shown) that senses when the power adaptor  20  has been connected to the mobile phone  30 . Upon detecting that the power adaptor  20  has been connected via the multifunction connector, the mobile phone  30  begins to be recharged via internal phone charging circuitry (not shown). At the same time, however, the mobile phone  30  is configured to enable operation of the radio receiver therein using, as explained in more detail below, the cable  32  of the power adaptor  20  as an antenna. The mobile phone  30  is then able to receive radio signals via the cable  32  and reproduce the radio signals via one or more speakers included in the mobile phone  30  and/or an auxiliary headset connector, etc. 
         [0048]      FIG. 4  illustrates the mobile phone  30  in accordance with the exemplary embodiment of the present invention. The mobile phone  30  includes a conventional mobile phone antenna  40  for receiving mobile phone signals from a communication tower, etc. The output of the antenna  40  is input to a mobile phone transceiver  42  that carries out conventional mobile phone communication operations. The mobile phone transceiver  42  further includes a conventional AM/FM radio transceiver, or “module”, which demodulates received AM/FM radio signals. The transceiver  42  outputs the audio signals from the received AM/FM signals to a sound processor  44  included in the mobile phone  30 . The sound processor  44  typically normally provides the audio signals to the headset  12  via the multifunction connector  46 . In the case where the mobile phone  30  senses that the phone is connected to the power adaptor  20 , however, the sound processor  44  outputs the sound to one or more speakers  48  or an auxiliary headset connection (not shown) included in the mobile phone  30 . 
         [0049]    As far as listening to the radio using the headset  12 , the mobile phone  30  is conventional in that normally the headset  12  ( FIG. 1 ) is connected to the headset terminal of the multifunction connector  46  via the corresponding connector  22 . The sound processor  44  in turn takes the RF signals received via the headphone cable  16  and inputs the signals to an AM/FM RF input of the transceiver  42 . The transceiver  42  outputs the resultant audio signals back to the sound processor  44 , and the sound processor  44  in turn outputs the audio signals to the headset  12  via the headset terminal. 
         [0050]    The mobile phone  30  also includes conventional phone charging circuits  50  that function to charge a rechargeable battery  52  that provides operating power to the mobile phone  30 . In addition, the mobile phone  30  includes a microprocessor  54  configured using conventional techniques to provide overall control of the mobile phone  30  in order to carry out the functions described herein. 
         [0051]    Continuing to refer to  FIG. 4 , the cable  32  provides the battery charge current from the plug  34  to the mobile phone  30  via the connector  22  and multifunction connector  46 . The cable  32  includes at least a pair of electrical conductors (e.g., copper wires, etc.) that connect at respective terminals to corresponding positive and negative conductors  56  and  58  of the mobile phone  30 . The conductors  56  and  58  are coupled to and provide the battery charge current to the phone charging circuits  50  so that the battery  52  is charged in accordance with conventional techniques. 
         [0052]    Additionally, the mobile phone  30  includes decoupling circuitry in the form of a capacitor C 1  or the like. The capacitor C 1  serves to decouple any AM/FM radio frequency signals induced onto the conductors of the cable  32  and provides the RF signals to an AM/FM RF input of the transceiver  42 . The AM/FM receiver within the transceiver  42  in turn demodulates the received signals and delivers the audio signals to the sound processor  44  so that they may be reproduced via the speaker  48 . The capacitor C 1  is sized so as to provide low impedance coupling of the AM/FM RF signals from the conductor  56  and/or  58  to the RF input of the transceiver  42 , while blocking any DC components associated with the battery charge current delivered to the phone charging circuits  50 . 
         [0053]    Accordingly, the mobile phone  30  is able to receive and reproduce radio signals even when simultaneously being charged using the cable  32  of the power adaptor  20  as an antenna. In a preferred embodiment, the cable  32  is approximately 1500 millimeters (mm) long so as to form a half-wave antenna optimized approximately in the middle of the FM radio frequency band. In addition, the cable  32  may include one or more EMI-filters to improve performance and block low frequency noise as will be appreciated. 
         [0054]    The speaker(s)  48  may be the ear speaker used for carrying on a typical telephone conversation using the mobile phone  30 . Alternatively, the speaker(s)  48  may include the conference speaker included in some mobile phones for conducting hands-free conference type calls. Still further, the speaker(s)  48  may be speakers included in the mobile phone  30  and dedicated for use in reproducing audio from the radio receiver or other audio media source in the mobile phone  30 . 
         [0055]      FIG. 5  illustrates another embodiment of the invention in which a docking station  60  serves as a base in which the mobile phone  30 . The docking station  60  allows the mobile phone  30  to be recharged yet still receive and play radio signals. As is shown in  FIG. 5 , the docking station  60  replaces the connector  22  in the power adaptor  20 . The docking station  60  is designed with it&#39;s own internal connector such that when the phone  30  is inserted into the docking station  60 , the multifunction connector  46  engages the internal connector of the docking station  60 . 
         [0056]    Referring to  FIG. 6  specifically, the docking station  60  receives the battery charge current via the positive and negative electrical conductors in the cable  32 . The docking station  60  couples the electrical conductors to the positive and negative conductors  56  and  58  of the phone  30 , respectively, via the internal connector of the docking station  60  and the multifunction connector  46  of the mobile phone  30 . The docking station  60  thereby provides the battery charge current to the phone charging circuits  50  in the manner described above in connection with the embodiment of  FIG. 4 . 
         [0057]    In the present embodiment, however, the mobile phone  30  does not necessarily include decoupling circuitry such as the capacitor C 1  in  FIG. 4 . Rather, the docking station  60  itself includes decoupling circuitry such as a capacitor C 2  that, similar to the capacitor C 1  in the embodiment of  FIG. 4 , decouples any RF signals induced on the cable  32 . More particularly, the capacitor C 2  is coupled at one end to the positive and/or negative conductor from the cable  32 . The other end of the capacitor C 2  is coupled via the internal connector to the headset terminal in the mobile phone  30  that otherwise would serve as the antenna input in the case where the cable  16  of the headset  12  serves as the antenna for mobile phone  30 . The RF signals decoupled from the cable  32  are therefore provided to the AM/FM RF input of the receiver circuit in the transceiver  42  in the same manner as they would be provided from the headset  12 . This eliminates the need for modifying a conventional mobile phone as in  FIGS. 1 and 2  to include decoupling circuitry. 
         [0058]    As in the previous embodiment, the capacitor C 2  is sized so as to represent a relatively low impedance to signals in the RF band, yet block any DC component associated with the battery charge current also provided via the cable  32 . Again, EMI filters may be included at the end(s) of the cable  32  or elsewhere to provide filtering as will be appreciated. 
         [0059]    As further represented in  FIG. 6 , the mobile phone  30  provides the left and right channel audio signals back to the docking station  60  via the headset terminals in the respective internal connector and multifunction connector  46 . The radio receiver within the transceiver  42  demodulates the RF signals input via the capacitor C 2  and provides the left and right channel audio signals. These left and right audio signals are input to respective differential audio amplifiers OPL and OPR included in the docking station  60 . In this particular embodiment, the capacitor C 2  is coupled to the negative conductor or the cable  32  and provides a common reference to the amplifiers OPL and OPR through an RF choke inductor L 1 . The amplifiers OPL and OPR amplify the respective audio signals and reproduce them through speakers  62  also included in the docking station  60 . The gain of the amplifiers OPL and OPR may be controlled using a volume control  64  as will be further appreciated. 
         [0060]    The inductor L 1  specifically serves to block the RF signal decoupled by the capacitor C 2  from being decoupled to the system ground at AM/FM frequencies (e.g., via the amplifiers OPL and OPR). In addition, inductors L 2  and L 3  are provided in the positive and negative conductors  56  and  58 , respectively, as shown in  FIG. 6 . Inductors L 2  and L 3  serve to block the RF signals induced on the cable  32  from being decoupled to the system ground at AM/FM frequencies (it will be appreciated that the inputs to the phone charging circuits  50  ( FIG. 4 ) are equal to ground at AM/FM frequencies). In addition, the inductors L 2  and L 3  protect against noise originating from the docking station  60  and/or mobile phone  30  from being coupled to the RF receiver input of the mobile phone  30 . Thus, the present invention allows for AM/FM signals induced on the cable  32  to be input to the RF receiver input of the mobile phone  30  while maintaining a high input impedance at the input of the RF receiver, as is desirable. Although not specifically shown, the inductors L 1 -L 3  may similarly be included in the embodiment of  FIG. 4  for similar purposes. 
         [0061]    The docking station  60  therefore can serve both to recharge a portable electronic device such as the mobile phone  30 , and simultaneously provide an antenna to the radio receiver within the mobile phone  30 . Still further, the docking station  60  eliminates the need for providing decoupling circuitry in the mobile phone  30  itself. Moreover, the docking station  60  may be used as an external audio amplifier and speaker system separate and apart from the mobile phone  30 . As a result, the playing of the radio can draw power mostly from the docking station  60 . This reduces the power draw from the battery  52  within the mobile phone  30 . In addition, the use of external amplifiers OPL/OPR and speakers  62  can provide improved listening fidelity as will be appreciated. 
         [0062]    Briefly referring to  FIG. 7 , another embodiment of the docking station  60  is shown. In this embodiment, the mobile phone  30  need not even include an RF receiver in the transceiver  42 . Rather, the docking station  60  in this embodiment includes its own radio receiver  70 . The capacitor C 2  decouples the RF signals induced onto the cable  32  and inputs the signals into the AM/FM RF input of the radio receiver  70 . Audio signals derived from the RF signals are then output from the radio receiver  70  to the respective left and right channel amplifiers OPL and OPR. Thus, in addition to providing a means for recharging the mobile phone  30  the docking station  60  also provides radio reception to mobile phones  30  that do not otherwise include a radio receiver. 
         [0063]    It will be appreciated that in another embodiment of the invention, the docking station  60  does not need to include its own speakers  62 . The docking station  60  may instead include its own headset jack for receiving a headset. Alternatively, the docking station  60  and/or mobile phone  30  may be configured to reproduce the audio signals using the speaker(s)  48  included in the mobile phone  30  itself. 
         [0064]    The present invention has been described primarily in the context of a portable electronic device that is a mobile phone  30 . However, the present invention is not limited to such type of portable electronic device in the broadest sense of the invention. The portable electronic device can be any type of device without departing from the scope of the invention. 
         [0065]    The present invention has also been described primarily in the context of a docking station serving as an accessory for both charging the portable electronic device and providing an antenna via its cable. It will be appreciated, though, that other types of accessories are also contemplated as being within the scope of the invention. 
         [0066]    The term “electronic device” as referred to herein includes a portable radio communication device. The term “portable radio communication device”, also referred to herein as a “mobile radio terminal”, includes all device such as mobile phones, pagers, communicators, e.g., electronic organizers, personal digital assistants (PDAs), smartphones or the like. In the present application, the invention is described primarily in the context of a mobile phone. However, it will be appreciated that the invention is not intended to be limited to a mobile phone and can be any type of portable electronic device. 
         [0067]    Although the invention has been shown and described with respect to certain preferred embodiments, it is obvious that equivalents and modifications will occur to others skilled in the art upon the reading and understanding of the specification. The present invention includes all such equivalents and modifications, and is limited only by the scope of the following claims.